The structure of
an atom is the basic unit of matter consisting of a nucleus and its
negatively charged electron cloud surrounding it. The nucleus contains a mix of positively charged
protons and electrically neutral neutrons (except in Hydrogen-1 which
has no neutrons). The electrons in an
atom bound to the nucleus by the electromagnetic force. Similarly, a collection of atoms can bind to
each other to form a molecule. Atoms containing the number of protons and
electrons of the same neutral, while containing the number of protons
and electrons of different positive or negative and is ion. Atoms are grouped based on the number of protons
and neutrons in the atomic nucleus. The number of protons in an atom
determines the chemical element the atom, and the number of neutrons
determine the isotope of the element.
PARTICLE MATERIALThe smallest part of matter called particles.Some opinions about
particles of matter:1. According
to Democritus, the distribution of matter is discontinuous (if the
material is divided and continues to be divided then finally obtained
the smallest particle that could no longer be divided = called Atom)2. According to Plato and Aristotle, the distribution of matter is
continuous (division can continue indefinitely)Basic Postulates of
Dalton Atomic Theory:1) All matter is composed of minute
particles called atoms2) The element is composed of material
similar atoms3)
Atoms of an element are identical but different from atoms of other
elements (having different masses)4) The compound is a material consisting of two
or more types of atoms with a certain ratio5) Atoms can not be
created or destroyed and can not be converted to other atoms through
chemical reactions normal. The chemical reaction is the rearrangement (reorganization) of
the atoms involved in the reaction
The downside of Dalton Atomic theory
postulates:1) Atom is not
something that is not divided, but rather made up of subatomic particles2) Atoms of the same element may have
different masses (called isotopes)3)
Atoms of an element can be changed into atoms of other elements through
nuclear reactions4) Some of the
elements are not made up of atoms instead of molecules
ATOMIC THEORY DEVELOPMENT1). Atomic Model
Daltona) Atom described as a very small solid ball.b) Atoms are the smallest particles that can not be broken again.c) Atoms of an
element have the same same, while the atoms of different elements,
different in mass and nature.d) Compounds are formed
when atoms combine with each other.e) A chemical reaction is the
reorganization of atoms, so there is no atom has changed due to chemical
reactions.
Dalton's atomic theory is supported by the second
law of nature, namely:1. Law of Conservation of Mass (Lavoisier
law): the mass of substances before and after the reaction is the same.2. Keep Comparative Law (law Proust): comparison of mass elements
that make up a substance is fixed.Weakness Atomic Model Dalton:1) Can not explain the difference between a
single atom elements with other elements2) Can not explain the
electrical properties of materials3) Can not explain how
atoms bond together4) According
to Dalton's atomic theory of number 5, no atom has changed due to
chemical reactions. Now it turns
out the reactions of nuclear chemistry, an atom can change into other
atoms.2). Thomson Atomic ModelAfter the
discovery of the electron by JJ Thomson, Thomson atomic model formulated
which is a refinement of the atomic model of Dalton. According to Thomson:a) Atoms consist
of a positively charged material and in which the electrons are
scattered (like raisins in raisin bread)b)
Atoms are neutral, the positive charge and negative charge the same
amount
3). Rutherford Atom Modela) Rutherford found
evidence that the atomic nuclei are positively charged, are smaller than
the size of the atomic mass of an atom but almost entirely from the
point masses.b) Atoms consist of a
positively charged nucleus and are at the center of the atom and the
electrons move through the nucleus (like planets in the solar system).c) Atoms are neutral.d) The radius of the nucleus and atomic radii can be
determined.Weakness
Rutherford Atomic Model:Ø Inability to explain why the
electrons do not fall into the nucleus due to electrostatic attractive
forces the core to the electron.Ø According to Maxwell's theory, if the electrons as
charged particles around the core that has the opposite charge then the
trajectory will spiral and will lose power / energy in the form of
radiation and eventually fell to the core.4).
Niels Bohr Atom Model• atomic model based on quantum theory to
explain the spectrum of hydrogen gas.• According to Bohr, the
line spectrum indicates that the electrons only occupy certain energy
levels in the atoms.He said:a) Atoms
consist of a positively charged nucleus and the surrounding circulating
electrons are negatively charged.b) Electrons orbit around the nucleus of an atom in a
particular orbit known as the stationary state of motion (fixed),
hereinafter referred to as the main energy level (electron shell), which
is expressed by the principal quantum number (n).c) During the
electrons are in a stationary orbit, its energy will remain so no light
is emitted.d) The electrons can only move from
the lower stationary trajectory to a higher stationary trajectory if
absorbing energy. Conversely, if the electrons move from a higher
stationary trajectory to lower the release of energy.e) In
the normal state (without outside influence), the electrons occupy the
lowest energy level (called the basic level = ground state)Niels Bohr Atom Model
Weaknesses:1. Just to explain the spectrum of the atom or ion containing one
electron and is not in accordance with the spectrum of electron atoms
or ions that much.2. Not being able to explain that atoms can form
molecules through chemical bonds5). Modern Atomic ModelDeveloped based on the
theory of quantum mechanics is called wave mechanics; initiated by 3
experts:a) Louis
Victor de BroglieStating
that the material has the properties of a material dualism, and as
waves.b) Werner HeisenbergPut forward the principle of
uncertainty for the material is of a particle and a wave. Distance or
location of electrons that surround the nucleus can only be determined
by the possibility - probability alone.c) Erwin Schrodinger
(refining models Bohr Atom)Successfully prepared for electron wave equation using the
principle of wave mechanics. Electrons surrounding the nucleus
contained in an area that is 3-dimensional orbital around the nucleus
where electrons with a specific energy can be found with the greatest
possible.Modern atomic
models:a) Atoms consist of a nucleus containing protons
and neutrons while the electrons moving around the nucleus and are at
particular orbitals of atoms that make up the skin.b)
the area of the 3-dimensional orbital around the nucleus where
electrons with a specific energy can be found with the greatest
possible.c) The position
of electrons in the orbital-orbital quantum numbers stated.•
Orbital described as a cloud of electrons, namely: the forms of space
where an electron is likely to be found.• The meeting of the electron cloud, the more
likely the electron was discovered and vice versa.
Minggu, 28 Oktober 2012
Kamis, 18 Oktober 2012
Energy and chemical reaction "enthalpy" (Ch 5)
Enthalpy
is a term in thermodynamics that states the amount of internal energy
of a thermodynamic system plus the energy used to do work. Enthalpy can not be measured, which can be calculated is the value changes. Mathematically, the enthalpy change can be formulated as follows:ΔH = ΔU + PΔVwhere:• H = enthalpy of the system (joules)• U = internal energy (joules)• P = pressure of the system (Pa)• V = volume of the system ()
1. System and environmentThe system is at the center of everything we learn concern the energy changes. While the so-called environment is everything outside the system. Example: The reaction between zinc metal with a solution of hydrochloric acid (HCl) in a test tube is accompanied by the emergence of gas bubbles.
In the example above the center of attention is the metal zinc and HCl. Thus, zinc metal and HCl solution called the system, while the test tube, air temperature, air pressure is the environment. Based on interaction with the environment, the system can be divided into three kinds, namely:a. Sitem Open, a system that allows the exchange of heat and matter (material) between the environment and the system.b. Closed system, a system which allows the exchange of heat between the system and its environment, but not an exchange of material.c. Isolated Systems (sealed), a system that does not allow the exchange of heat and matter between the system and the environment.
2. Energy and enthalpyIn any chemical reaction is always a change of energy.Energy units:1 calorie = 4.184 Joules1 kJ = 1000 Joules1 kcal = 1000 calories1kkal = 4.184 k JOverall energy possessed by a system in a particular state is called energy (U). Energy in a state function, depends only on the state of the system (temperature, volume, pressure, and number of moles), does not depend on the path through the system. Energy can not be measured but the changes can be measured. If the change occurs at a constant pressure (open system), the energy changes that occur in the so-called enthalpy change.
Chemical reactions are generally carried out in an open system (fixed pressure).Therefore, in any process that involves a change in volume due to constant pressure, there is the work that accompanies the process although a small but significant.According to the Law of Thermodynamics I (Law of Conservation of Energy),H = U + PVThe enthalpy change is expressed by the equation:H = U + PVFrom the equation it can be concluded that if the reaction is carried out at a constant pressure the heat changes that occur will be equal to the enthalpy change for the pressure change 0 (Zero). Thus, the enthalpy equal to the amount of energy stored in a system. So the enthalpy (H) is the energy stored in the form of heat in a system.
3. Enthalpy changeThe enthalpy change of a system can be measured if the system is changing.Enthalpy changes (H):If a reaction takes place at a constant pressure, the change in enthalpy equalthe heat that must be removed from the system into the environment or otherwise thattemperature of the system back to its original state.H = qp (qp = heat of reaction at constant pressure)The magnitude of the enthalpy change is the difference in magnitude of the enthalpy of the system after a change in the magnitude of the enthalpy of the system before the changes at a constant pressure.H = Hakhir - HawalThe enthalpy change accompanying a reaction is influenced by:• The number of substances• physical state of a substance• Temperature (T)• Pressure (P)
4. Reaction was exothermic and endothermic reactions1. Exothermic reaction is a reaction that releases heat or energy.Enthalpy reduced system (the reaction products have a lower enthalpy than the original substance).H final <H initialH final - H initial <0H negative valueExample:The reaction between calcium oxide (quicklime) and Cretaceous shallow water put into the water in a test tube. This reaction takes place is characterized by a mixture of temperature rise (the system). Because the temperature of the system is higher than the environment, the heat will come out of the system into the environment until they become the same temperature.CaO (s) + H2O (l) Ca (OH) 2 (aq)
2. Endothermic reaction is a reaction that absorbs heat or energy needs.Enthalpy system is improved (the reaction has a higher enthalpy than the original substance).H final> H initialH final - H initial> 0H positive valueExample:The reaction between barium hydroxide crystals oktahidrat with ammonium chloride crystals.When barium hydroxide crystals oktahidrat, Ba (OH) 2. 8H2O crystals mixed with ammonium chloride (NH4Cl), the reaction takes place immediately marked by a drop in temperature and the formation of a mixture of ammonia gas. Therefore temperature of the mixture (the system) will be lower than the environment, the heat will flow from the environment into the system until they become the same temperature. Ba (OH) 2. 8H2O (s) + 2NH4Cl BaCl2.2H2O (s) + 2NH3 (g) + 8H2O (l)
5. Thermochemical EquationsThe equation that describes the reaction with the information about the change in enthalpy (heat). Because enthalpy is extensive properties (value depends on the magnitude and size of the system) then the thermochemical equation also listed the number of moles of a substance expressed reaction coefficient, and the phase state of the substance involved.Example:a. In the formation of 1 mol of water from hydrogen gas with oxygen gas at 25 ° C(298 K), 1 atm, was 286 kJ of heat is released.Thermochemical equations of the above statement isThe word "released" state that quite exothermic reaction. Therefore, theH = -286 kJ per mole of water formed.H2 (g) + O2 (g) H2O () H = -286 kJor,2H2 (g) + O2 (g) 2H2O () H = -572 kJ
b. The reaction of carbon and hydrogen to form 1 mole of C2H2 at temperatures of 25oCand a pressure of 1 atm requires 226.7 kJ of heat.Termokimianya equation:The word "need" states that belong to endothermic reactions.2 C (s) + H2 (g) C2H2 (g) + H = 226.7 kJ
6. Standard enthalpy change (Ho)Reaction enthalpy changes measured at 25oC temperature (298 K) andpressure of 1 atm was agreed as the standard enthalpy change, otherwisewith the symbol HoThe state standard is needed because measurements at different temperatures and pressures will result in prices that different enthalpy changes. Units used to express the change in enthalpy is kJ. Changes in molar enthalpy is kJ / mol.
Enthalpy change based on the type of chemical changes that occur:1. Standard enthalpy change of formation (Hf o)(Hf o = standard enthalpy of formation)Is the enthalpy change for the formation of 1 mole of a compound from its elements are the most stable, the standard state. Unit change in standard enthalpy of formation according to the International System (SI) is kJ / mol.Example:Changes from the standard enthalpy of formation of carbon dioxide (CO2) is -393.5 kJ / mol.Termokimianya equation:C (s) + O2 (g) CO2 (g) Hfo = -393.5 kJ / mol
2. Standard enthalpy change of decomposition (Hd o)(Hd o = standard enthalpy of decomposition)Is the enthalpy change for the decomposition of 1 mole of a compound into its elements, the standard state.Example:Enthalpy change for the decomposition of H 2 O is +286 kJ / mol.Termokimianya equation:H2O () H2 (g) + O2 (g) Hdo = + 286 kJ / mol
3. Standard enthalpy change of combustion (Hc o)(Hc o = standard enthalpy of combustion)Is the change in enthalpy in the combustion of 1 mol element or compound at standard conditions. Combustion is the reaction of a substance with oxygen
1. System and environmentThe system is at the center of everything we learn concern the energy changes. While the so-called environment is everything outside the system. Example: The reaction between zinc metal with a solution of hydrochloric acid (HCl) in a test tube is accompanied by the emergence of gas bubbles.
In the example above the center of attention is the metal zinc and HCl. Thus, zinc metal and HCl solution called the system, while the test tube, air temperature, air pressure is the environment. Based on interaction with the environment, the system can be divided into three kinds, namely:a. Sitem Open, a system that allows the exchange of heat and matter (material) between the environment and the system.b. Closed system, a system which allows the exchange of heat between the system and its environment, but not an exchange of material.c. Isolated Systems (sealed), a system that does not allow the exchange of heat and matter between the system and the environment.
2. Energy and enthalpyIn any chemical reaction is always a change of energy.Energy units:1 calorie = 4.184 Joules1 kJ = 1000 Joules1 kcal = 1000 calories1kkal = 4.184 k JOverall energy possessed by a system in a particular state is called energy (U). Energy in a state function, depends only on the state of the system (temperature, volume, pressure, and number of moles), does not depend on the path through the system. Energy can not be measured but the changes can be measured. If the change occurs at a constant pressure (open system), the energy changes that occur in the so-called enthalpy change.
Chemical reactions are generally carried out in an open system (fixed pressure).Therefore, in any process that involves a change in volume due to constant pressure, there is the work that accompanies the process although a small but significant.According to the Law of Thermodynamics I (Law of Conservation of Energy),H = U + PVThe enthalpy change is expressed by the equation:H = U + PVFrom the equation it can be concluded that if the reaction is carried out at a constant pressure the heat changes that occur will be equal to the enthalpy change for the pressure change 0 (Zero). Thus, the enthalpy equal to the amount of energy stored in a system. So the enthalpy (H) is the energy stored in the form of heat in a system.
3. Enthalpy changeThe enthalpy change of a system can be measured if the system is changing.Enthalpy changes (H):If a reaction takes place at a constant pressure, the change in enthalpy equalthe heat that must be removed from the system into the environment or otherwise thattemperature of the system back to its original state.H = qp (qp = heat of reaction at constant pressure)The magnitude of the enthalpy change is the difference in magnitude of the enthalpy of the system after a change in the magnitude of the enthalpy of the system before the changes at a constant pressure.H = Hakhir - HawalThe enthalpy change accompanying a reaction is influenced by:• The number of substances• physical state of a substance• Temperature (T)• Pressure (P)
4. Reaction was exothermic and endothermic reactions1. Exothermic reaction is a reaction that releases heat or energy.Enthalpy reduced system (the reaction products have a lower enthalpy than the original substance).H final <H initialH final - H initial <0H negative valueExample:The reaction between calcium oxide (quicklime) and Cretaceous shallow water put into the water in a test tube. This reaction takes place is characterized by a mixture of temperature rise (the system). Because the temperature of the system is higher than the environment, the heat will come out of the system into the environment until they become the same temperature.CaO (s) + H2O (l) Ca (OH) 2 (aq)
2. Endothermic reaction is a reaction that absorbs heat or energy needs.Enthalpy system is improved (the reaction has a higher enthalpy than the original substance).H final> H initialH final - H initial> 0H positive valueExample:The reaction between barium hydroxide crystals oktahidrat with ammonium chloride crystals.When barium hydroxide crystals oktahidrat, Ba (OH) 2. 8H2O crystals mixed with ammonium chloride (NH4Cl), the reaction takes place immediately marked by a drop in temperature and the formation of a mixture of ammonia gas. Therefore temperature of the mixture (the system) will be lower than the environment, the heat will flow from the environment into the system until they become the same temperature. Ba (OH) 2. 8H2O (s) + 2NH4Cl BaCl2.2H2O (s) + 2NH3 (g) + 8H2O (l)
5. Thermochemical EquationsThe equation that describes the reaction with the information about the change in enthalpy (heat). Because enthalpy is extensive properties (value depends on the magnitude and size of the system) then the thermochemical equation also listed the number of moles of a substance expressed reaction coefficient, and the phase state of the substance involved.Example:a. In the formation of 1 mol of water from hydrogen gas with oxygen gas at 25 ° C(298 K), 1 atm, was 286 kJ of heat is released.Thermochemical equations of the above statement isThe word "released" state that quite exothermic reaction. Therefore, theH = -286 kJ per mole of water formed.H2 (g) + O2 (g) H2O () H = -286 kJor,2H2 (g) + O2 (g) 2H2O () H = -572 kJ
b. The reaction of carbon and hydrogen to form 1 mole of C2H2 at temperatures of 25oCand a pressure of 1 atm requires 226.7 kJ of heat.Termokimianya equation:The word "need" states that belong to endothermic reactions.2 C (s) + H2 (g) C2H2 (g) + H = 226.7 kJ
6. Standard enthalpy change (Ho)Reaction enthalpy changes measured at 25oC temperature (298 K) andpressure of 1 atm was agreed as the standard enthalpy change, otherwisewith the symbol HoThe state standard is needed because measurements at different temperatures and pressures will result in prices that different enthalpy changes. Units used to express the change in enthalpy is kJ. Changes in molar enthalpy is kJ / mol.
Enthalpy change based on the type of chemical changes that occur:1. Standard enthalpy change of formation (Hf o)(Hf o = standard enthalpy of formation)Is the enthalpy change for the formation of 1 mole of a compound from its elements are the most stable, the standard state. Unit change in standard enthalpy of formation according to the International System (SI) is kJ / mol.Example:Changes from the standard enthalpy of formation of carbon dioxide (CO2) is -393.5 kJ / mol.Termokimianya equation:C (s) + O2 (g) CO2 (g) Hfo = -393.5 kJ / mol
2. Standard enthalpy change of decomposition (Hd o)(Hd o = standard enthalpy of decomposition)Is the enthalpy change for the decomposition of 1 mole of a compound into its elements, the standard state.Example:Enthalpy change for the decomposition of H 2 O is +286 kJ / mol.Termokimianya equation:H2O () H2 (g) + O2 (g) Hdo = + 286 kJ / mol
3. Standard enthalpy change of combustion (Hc o)(Hc o = standard enthalpy of combustion)Is the change in enthalpy in the combustion of 1 mol element or compound at standard conditions. Combustion is the reaction of a substance with oxygen
Kamis, 11 Oktober 2012
STOICHIOMETRIC (CH4)
Stoichiometric
A. Tata Compound Name
1. Nomenclature of Inorganic CompoundsThe nomenclature of inorganic compounds are generally grouped into two, namely:a. Naming Binary CompoundsBinary compound is a compound composed of two types of elements.• Binary Ionic CompoundsBinary compound of a metal and a metal ion compounds. Ionic compound consisting of positive ions (cations) which is a metal ion and a negative ion (anion) which is a non-metallic ions.Table cations and anions of Binary Compounds Metals and non-metalsType Ion Ion Formula Formula Ion Name Ion Name IonCations Na + Fe3 + Sodium Iron (III)Potassium K + Cu + Copper (I)Magnesium Mg 2 + Cu 2 + Copper (II)Ca2 + Calcium Co2 + cobalt (II)Ba2 + + CO3 Barium Cobalt (III)Al3 + + SN2 Aluminium Tin (II)Ni2 + Nickel + SN4 Tin (IV)Zn2 + Pb2 + Zinc Lead (II)Pb4 Ag + Silver + Lead (IV)F-Fluoride anion H-HydrideCl-Chloride-Oxide O2Br-Bromide S2-sulfideI-N3-Nitride IodidesMetal and non-metal binary compounds are neutral (uncharged), meaning that the charge of cations and anions are equal or the charge on the cation and anion in a compound is zero.In General: Ay +AxByBx-Ay + ions bind to the ion Bx AxBy-forming ionic compounds, the ion charge an index Ay + Bx-B and charge an index A.Writing rules and naming binary compounds and metals and non-metals are as follows:1) Writing formulas of compounds, cations cations in front and behind.2) The metal ion has only one charge (electric charge), the naming of compounds is the name of the metal ion in the front and the name behind non-metallic ions. Metal whice like this is an alkali metal (IA), alkaline earth (IIA), and aluminum.3) metal ions have multiple charges (electric charge), Naming compounds is the name on the front of the metal ions with the ionic charge by writing to the Roman numerals in parentheses, while the name of the non-metallic ions behind.The compound belongs to the binary compounds of metals and non-metals, namely;1) Compound SaltsSalt compound obtained from the reaction between an acid with a base. The salt compound is formulated as follows.Salt compound is formed from metal ions and ion rest Ly + Ax acid-forming salts LxAy2) Oxidation of Metals (Oxidation Basa)Oxidation of metal is an alkaline forming in water oxidation. Oxidation of metal formula is as follows.The compound is formed from the oxidation of metal ions and metal ions Ox + Ly-forming metal oxide compounds.Table Name Oxidation Metals and Basa are FormedOxidation of Metals Oxidation name formed Metal BasesLithium oxide Li2O LiOHSodium oxide Na2O NaOHK2O potassium oxide KOHMagnesium oxide MgO Mg (OH) 2Strontium Oxide SrO Sr (OH) 2Barium oxide BaO Ba (OH) 2Aluminium oxide Al2O3 Al (OH) 3Cr2O3 Chromium (III) oxide Cr (OH) 3FeO Iron (II) oxide Fe (OH) 2Fe2O3 Iron (III) oxide Fe (OH) 3• non-metallic and non-metallic Binary Compounds (Covalent Compounds)Non-metallic with non-metallic compounds are binary covalent compounds. The smallest particle of a compound is a molecule. Covalent compounds can be formulated as follows.
A and B are non-metals. Elements of A are more likely to positively charged and the element B is more likely to negatively charged. The letter x is the index of the element of A, ie the number of atoms making up the molecules A AxBy. The letter y is the index of the element of B, B is the number of atoms making up the molecules AxBy. Formation of molecular compounds AxBy by sharing electron pairs.Writing and naming rules binary compounds between non-metallic and non-metallic (covalent compounds) are as follows.1) For the positively charged atoms that tend to be written on the front and the negatively charged atoms that tend to be written on the back.Example: N to O, the formula N2O compounds not On22) For non-metallic compound which forms only one compound, its name is the name of the second element and the second element are given the suffix ida.Example:HCL: Hydrogen ChlorideH2S: Hydrogen Sulfide3) For non-metallic compounds that can form two or more compounds, naming naming as above, but each is given a prefix that states the number of atoms of each element and ending with ida. Prefix is a Greek index numbers. Prefix used is as follows.1 = mono2 = on3 = tri4 = tetra5 = penta6 = hex7 = hepta8 = octaExample:N2O: Nitrous monoxideNO: Nitrogen monoxideNO2: nitrogen dioxideNote:The prefix mono is not used on the front element that lies ahead, such as NO2 do not need to read mononitrogen dioxide.4) The compound is a common and well-known not following the rules above.Example:H2O: WaterNH3: AmmoniaBinary covalent compounds composed of amino compounds and oxides of non-metals monoksi.1) Acid Compounds NonoksiAccording to Arrhenius, an acid is a substance that can release H + ions in water. This is called the amino acid nonoksi Because it does not contain an acidic oxide. In contrast, amino acid-containing oxide is an acidic oxide.Naming nonoksi acid compound can be written as follows.
Example:HF: florida acidHCl: hydrochloric acidHbr: hydrogen bromideHI: Acid IonidaNote:HCN is not a binary compound, but its name as nonoksi acid. Naming HCN is hydrogen cyanide.2) Oxides of non-metalsOxide is a compound of an element with oxygen. Oxides of non-metals non-metals are oxides which, when dissolved in water to form acidic compounds. Non-metallic oxide is also called acid oxide. However, not all non-metallic oxides including acidic oxide. The general formula is as follows-metallic oxides.
The naming of non-metallic oxide has been described in naming non-metallic and non-metallic binary compounds.Major non-metallic non-metallic oxide Acid oxide formedSulfur dioxide SO2 H2SO3Sulfur trioxide SO3 H2SO4Dinitrogen trioxide N2O3 HNO2HNO3 N2O5 dinitrogen pentaoksidaDifosfor trioxide H3PO3 P2O3Difosfor pentaoksida H3PO4 P2O5b. Naming polyatomic compoundsPolyatomic compounds are compounds composed by more than two types of elements. Polyatomic compound consists of:• Ionic compounds polyatomicPolyatomic ionic compounds are compounds polyatomic ions which are the smallest particles. Polyatomic ionic compound composed of cations and anions, namely:1) Compound Salts of polyatomicThe salt compound is a compound salt polyatomic cation or anion is polyatomic ion.2) Basa CompoundAccording to Arrhenius, bases are substances that can release OH-ions in water. Base solution slightly bitter taste and is kausatik (slippery as soap). Basic compounds are ionic compounds consisting of metal cations and anions OH-(except NH4OH). Basic compounds can be formulated as follows.
L: metalOH-: hydroxide (the nature of base)x: valence basa (similar to numbers oxide L)Naming the basic compounds are as follows: alkaline compounds formed by a metal ion yng have sole charge. For example, alkali, alkaline earth metals, and aluminum. Naming compounds are formulated as follows:
base formed by the metal ions have multiple charges, naming compounds are formulated as follows:
• Covalent compounds polyatomicPolyatomic covalent compound is a compound that polyatomic molecule is the smallest particle. The compound belongs to the polyatomic covalent compound is a compound oxyacid.Naming oxyacid compounds are as follows.1) the only non-metallic elements form a compound, the compound ends-at.2) non-metallic element that forms two types of amino acid, which has a lot of oxygen ends-at.3) oxy-halogen acid is an acid that has an acidic oxide and a halogen oxides. In simple terms, means oxyacid halogen atom acid center is the halogen elements. Naming acids halogen oxides depends on the oxidation state or the amount of oxygen.2. Nomenclature of Organic Compoundsa. Simple Hydrocarbon CompoundsHydrocarbon compounds are classified as alkanes, alkenes, and alkynes. The division of these compounds is based on the existence of double bonds in the hydrocarbon compounds.IUPAC nomenclature for alkenes and alkynes compounds based on the nomenclature of alkanes with the number of C atoms corresponding to the change akhirannya match the name of each compound.Comparison of Names Simple Organic CompoundsNumber of atoms C Name Alkanes Alkenes Name Name alkyne1 Methane -2 Ethane Ethene ethyne3 Propane propene Propuna4 Butane Butene ButunaPentane 5 Pentena Pentuna6 Hexane hexene Heksuna7 heptane Heptena Heptuna8 octane octene Oktuna9 Nonana Nonena Nonuna10 decane Dekena Dekunab. Simple Alcohol CompoundsTata nana alcohol compound similar to the nomenclature of simple hydrocarbons. Naming, modest alcohol compounds are as follows.CH3OH: MethanolC2H5OH: EthanolC3H7OH: Propanolc. Organic Acid CompoundsOrganic acids or carboxylic acids by IUPAC called alkanoic acids. General formula is R-COOH. Naming sorted as follows.R (alkyl) is an alkane missing one atom H.B. The law - the law of Basic Chemicals
• LAW OF CONSERVATION OF MASS (Lavoisier LAW)"The mass of substances before and after the reaction is fixed".Example:hydrogen + oxygen = hydrogen oxide(4g) (32g) (36g)
• FIXED COMPARATIVE LAW (LAW Proust)"Comparison of the mass of the elements in each compound is fixed"Example:a. In the compound NH3: N mass: mass of HAr = 1. N: 3 Ar. H= 1 (14): 3 (1) = 14: 3b. On the compound SO3: S mass: mass 0Ar = 1. S: 3 Ar. O= 1 (32): 3 (16) = 32: 48 = 2: 3Advantages of the law Proust:if known mass of a compound or a mass of one of the elements that make up the compound is the mass of other elements could be determined.Example:How many levels of C in 50 grams of CaCO3? (Ar: C = 12; 0 = 16; Ca = 40)Mass C = (Ar C / Mr CaCO3) x mass of CaCO3= 12/100 x 50 grams = 6 gramsmass CLevels of C = mass C / mass x 100% CaCO3= 6/50 x 100% = 12%
Deviations from the law Proust
Please note that while this law is very useful in the fundamentals of modern chemistry, comparative law still does not always apply to all compounds. Compounds that do not comply with this law are called non-stoikiometris compounds. Mass ratio of the elements in the non-stoikiometris compounds vary in different samples. For example, iron oxide wüstite, has a ratio of between 0.83 to 0.95 iron atoms for every oxygen atom. Proust did not know this because of the equipment he uses is not accurate enough to distinguish this figure.
In addition, the law also does not apply to Proust compounds containing different isotopic compositions. Isotopic composition may vary according to the source of the elements that make up the compound. This difference can be used to chemically calendar, because the processes astronomical, atmospheric, and processes in the oceans, Earth's crust and the inside is sometimes have a tendency toward heavy or light isotopes. Caused very little difference, but it can usually be measured with modern equipment. In addition, the law also does not apply Proust in polymers, both natural and artificial polymers polymers.
• LEGAL COMPOUND = COMPARATIVE LAW DALTON"When the two elements can form two or more compounds to the mass of one element as much the second element of the mass ratio in value as integers and simple".Example:If the element nitrogen fertilized den oxygen can be formed,NO where mass N: 0 = 14: 16 = 7: 8NO2 which the mass N: 0 = 14: 32 = 7: 16For the same amount of nitrogen mass ratio of the mass of oxygen in the compound NO: NO2 = 8: 16 = 1: 2
• GAS LAWS To apply the ideal gas equation: PV = nRTwhere:P = gas pressure (atmospheric)V = gas volume (liters)n = moles of gasR = universal gas constant = 0082 lt.atm / mol KelvinT = absolute temperature (Kelvin)The changes of P, V and T from state 1 to state 2 with certain conditions reflected by the following laws:
BOYLE LAW This law is derived from the ideal gas equation of state withn1 = n2 and T1 = T2; thus obtained: P1 V1 = P2 V2LEGAL Gay-Lussac"The volume of gases that react den gas volume of reaction when measured at the same temperature and pressure, will be compared as integers modest den".So for: P1 = P2 and T1 = T2 holds: V1 / V2 = n1 / n2BOYLE LAW-Gay LussacThis law is an extension of the previous law is spoken with the state price den n = n2 to obtain the equation:P1. V1 / T1 = P2. V2 / T2Avogadro's law"At the same temperature and pressure, gases equal volume containing the same number of moles. From this statement it is determined that the state of STP (0o C 1 atm) 1 mole of any gas volume of 22.4 liters of volume is referred to as the molar volume of gas.Example:What volume of 8.5 g of ammonia (NH3) at a temperature of 27o C and a pressure of 1 atm?(Ar: H = 1, N = 14)Answer:85 g of ammonia = 17 mol = 0.5 molThe volume of ammonia (STP) = 0.5 x 4.22 = 2.11 litersAccording to Boyle-Gay Lussac equation:P1. V1 / T1 = P2. V2 / T21 x 112.1 / 273 = 1 x V2 / (273 + 27). V2 = 12:31 litersC. Reaction Equations
Equation has the properties:1) Type of the elements before and after the reaction is always the same2) The number of each atom before and after the reaction is always the same3) Comparison of the reaction coefficient expressed mole ratio (ratio of specific gaseous volume ratio coefficient is also said as long as the same temperature and pressure)Step-by-Step Writing Reaction Equations1) The names of the reactants and reaction products listed. The writing is calledequality predicates.2) Write the equation using the symbols, iechemical formulas of substances, and the form of the reaction. The writing is called equality framework.3) Balance the equation to obtain the equation kerangksequivalent reaction is called chemical equation.Equivalency equationEquivalency equation Raksi lawful immune reaction Lavoisier and Dalton's atomic theory. According to the law of Lavoisier, the chemical reaction does not change the mass. That is, the number and type of atoms on the left (reactants) is equal to the number and type of atoms on the right (the reaction). As per Dalton's atomic theory, chemical reactions no atoms lost or created, all that happened was the rearrangement of the atoms forming reactants new arrangement, the reaction products. To be kind and number of atoms on the left the same as in the right-hand side, the equation equivalent (balanced) by arranging the numbers in front of the reactants and reaction products. Figures given in front of the reactants and reaction products are called coefficients. Number one as coefficient is omitted. Therefore, the equation can be written as follows.Stages equalization equation can be done by:1) Write the equation of the framework, which is not equivalent to the equation, the reactants on the left and the reaction on the right.2) Set the coefficient of the substance / compound is a more elaborate one.3) Balance the reaction by adjusting the coefficients of the reactants and reaction products to another.
D. Mol Concepts
mole is the amount of the chemical unit numbers of the atoms or molecules of Avogadro's number and mass = Mr compound.If Avogadro's number = L then:L = 6.023 x 10231 mole of atoms = L atoms, mass = Ar atom.1 mole of molecules = L = Mr fruits molecular mass of the molecule.The mass of one mole of a substance is called the molar mass of the substanceExample:How many molecules are present in 20 grams of NaOH?Answer:Mr NaOH = 23 + 16 + 1 = 40mol NaOH = mass / Mr = 20/40 = 0.5 molThe number of molecules of NaOH = 0.5 L = 0.5 x 6023 x 1023 = 3.01 x 1023 molecules.Mol relationship with the number of particlesIt is known that substances 1mol X = l fruit particles of matter X, then2 moles of substance X = 2 x L particles of substance X5 moles of substance X = 5 x L particles of substance Xn moles of substance X = n x L particles of substance XThe number of particles = n x L
Future Atom and The Formula1) Atomic MassAtomic mass is defined as the mass of an atom in atomic units of mass units (amu) or atomic mass units (sma). One amu is defined as 1/12 times the mass of one atom of C-12. Carbon-12 is one isotope of carbon has 6 protons and 6 neutrons. This element is used as a standard of comparison for these elements have properties that are very stable with long half-lives. By setting an atomic mass of 12 C-12 sma, we can determine the mass of atoms of other elements. For example, it is known that the hydrogen atom has a mass of only 8.4% of the mass of one atom of C-12. Thus, the mass of a hydrogen atom is 8.4% or 1.008 x 12 sma sma. By similar calculations, one can obtain the mass of the oxygen atom is 16.00 sma and an atomic mass of iron is 55.85 sma. This means that a single iron atom has a mass about 56 times the mass of a hydrogen atom.2) Relative Atomic Mass (Ar)Atomic mass of the element of truth can not be measured by weighing the mass of atoms, because atoms are so small. Atomic mass of the element is determined by comparing the average atomic mass of the element to 1/12 the average mass of one atom of carbon-12 so obtained is the atomic mass relative atomic mass (Ar).3) Relative Molecular MassElements and compounds in the form of molecular particle, its mass is expressed in relative molecular mass (Mr). Basically the relative molecular mass (Mr) is the ratio of the average mass of a single molecule of an element or compound with 1/12 the average mass of one atom of carbon-12.
So many types of molecules, so no table relative molecular mass. However, the relative molecular mass can be calculated by adding the relative atomic mass of the atoms that form the molecule.Mr = ΣArTo compound the particle is not shaped molecules, but pair ions, such as NaCl then Mr. compound called relative formula mass. Relative formula mass is calculated in the same way as the calculation of the relative molecular mass, ie by adding the relative atomic mass of the elements in the formula of the compound.4) Molar MassIt is known that a mole is the amount of substance containing particles (atoms, molecules, ions) as there are atoms in 12 grams of carbon with mass number 12 (carbon-12, C-12). So it looks that the mass of one mole of C-12 is 12 grams. The mass of one mole of a substance is called the molar mass. Molar mass equal to the relative molecular mass (Mr) or relative atomic mass (Ar) of a substance expressed in grams.Molar Mass = Mr or Ar a substance (g)
5) Molar VolumeAvogadro get the results of experiments that at a temperature of 0 ° C (273 K) and a pressure of 1 atmosphere (76cmHg) got exactly 1 liter of oxygen to the mass of 1.3286 grams.
A. Tata Compound Name
1. Nomenclature of Inorganic CompoundsThe nomenclature of inorganic compounds are generally grouped into two, namely:a. Naming Binary CompoundsBinary compound is a compound composed of two types of elements.• Binary Ionic CompoundsBinary compound of a metal and a metal ion compounds. Ionic compound consisting of positive ions (cations) which is a metal ion and a negative ion (anion) which is a non-metallic ions.Table cations and anions of Binary Compounds Metals and non-metalsType Ion Ion Formula Formula Ion Name Ion Name IonCations Na + Fe3 + Sodium Iron (III)Potassium K + Cu + Copper (I)Magnesium Mg 2 + Cu 2 + Copper (II)Ca2 + Calcium Co2 + cobalt (II)Ba2 + + CO3 Barium Cobalt (III)Al3 + + SN2 Aluminium Tin (II)Ni2 + Nickel + SN4 Tin (IV)Zn2 + Pb2 + Zinc Lead (II)Pb4 Ag + Silver + Lead (IV)F-Fluoride anion H-HydrideCl-Chloride-Oxide O2Br-Bromide S2-sulfideI-N3-Nitride IodidesMetal and non-metal binary compounds are neutral (uncharged), meaning that the charge of cations and anions are equal or the charge on the cation and anion in a compound is zero.In General: Ay +AxByBx-Ay + ions bind to the ion Bx AxBy-forming ionic compounds, the ion charge an index Ay + Bx-B and charge an index A.Writing rules and naming binary compounds and metals and non-metals are as follows:1) Writing formulas of compounds, cations cations in front and behind.2) The metal ion has only one charge (electric charge), the naming of compounds is the name of the metal ion in the front and the name behind non-metallic ions. Metal whice like this is an alkali metal (IA), alkaline earth (IIA), and aluminum.3) metal ions have multiple charges (electric charge), Naming compounds is the name on the front of the metal ions with the ionic charge by writing to the Roman numerals in parentheses, while the name of the non-metallic ions behind.The compound belongs to the binary compounds of metals and non-metals, namely;1) Compound SaltsSalt compound obtained from the reaction between an acid with a base. The salt compound is formulated as follows.Salt compound is formed from metal ions and ion rest Ly + Ax acid-forming salts LxAy2) Oxidation of Metals (Oxidation Basa)Oxidation of metal is an alkaline forming in water oxidation. Oxidation of metal formula is as follows.The compound is formed from the oxidation of metal ions and metal ions Ox + Ly-forming metal oxide compounds.Table Name Oxidation Metals and Basa are FormedOxidation of Metals Oxidation name formed Metal BasesLithium oxide Li2O LiOHSodium oxide Na2O NaOHK2O potassium oxide KOHMagnesium oxide MgO Mg (OH) 2Strontium Oxide SrO Sr (OH) 2Barium oxide BaO Ba (OH) 2Aluminium oxide Al2O3 Al (OH) 3Cr2O3 Chromium (III) oxide Cr (OH) 3FeO Iron (II) oxide Fe (OH) 2Fe2O3 Iron (III) oxide Fe (OH) 3• non-metallic and non-metallic Binary Compounds (Covalent Compounds)Non-metallic with non-metallic compounds are binary covalent compounds. The smallest particle of a compound is a molecule. Covalent compounds can be formulated as follows.
A and B are non-metals. Elements of A are more likely to positively charged and the element B is more likely to negatively charged. The letter x is the index of the element of A, ie the number of atoms making up the molecules A AxBy. The letter y is the index of the element of B, B is the number of atoms making up the molecules AxBy. Formation of molecular compounds AxBy by sharing electron pairs.Writing and naming rules binary compounds between non-metallic and non-metallic (covalent compounds) are as follows.1) For the positively charged atoms that tend to be written on the front and the negatively charged atoms that tend to be written on the back.Example: N to O, the formula N2O compounds not On22) For non-metallic compound which forms only one compound, its name is the name of the second element and the second element are given the suffix ida.Example:HCL: Hydrogen ChlorideH2S: Hydrogen Sulfide3) For non-metallic compounds that can form two or more compounds, naming naming as above, but each is given a prefix that states the number of atoms of each element and ending with ida. Prefix is a Greek index numbers. Prefix used is as follows.1 = mono2 = on3 = tri4 = tetra5 = penta6 = hex7 = hepta8 = octaExample:N2O: Nitrous monoxideNO: Nitrogen monoxideNO2: nitrogen dioxideNote:The prefix mono is not used on the front element that lies ahead, such as NO2 do not need to read mononitrogen dioxide.4) The compound is a common and well-known not following the rules above.Example:H2O: WaterNH3: AmmoniaBinary covalent compounds composed of amino compounds and oxides of non-metals monoksi.1) Acid Compounds NonoksiAccording to Arrhenius, an acid is a substance that can release H + ions in water. This is called the amino acid nonoksi Because it does not contain an acidic oxide. In contrast, amino acid-containing oxide is an acidic oxide.Naming nonoksi acid compound can be written as follows.
Example:HF: florida acidHCl: hydrochloric acidHbr: hydrogen bromideHI: Acid IonidaNote:HCN is not a binary compound, but its name as nonoksi acid. Naming HCN is hydrogen cyanide.2) Oxides of non-metalsOxide is a compound of an element with oxygen. Oxides of non-metals non-metals are oxides which, when dissolved in water to form acidic compounds. Non-metallic oxide is also called acid oxide. However, not all non-metallic oxides including acidic oxide. The general formula is as follows-metallic oxides.
The naming of non-metallic oxide has been described in naming non-metallic and non-metallic binary compounds.Major non-metallic non-metallic oxide Acid oxide formedSulfur dioxide SO2 H2SO3Sulfur trioxide SO3 H2SO4Dinitrogen trioxide N2O3 HNO2HNO3 N2O5 dinitrogen pentaoksidaDifosfor trioxide H3PO3 P2O3Difosfor pentaoksida H3PO4 P2O5b. Naming polyatomic compoundsPolyatomic compounds are compounds composed by more than two types of elements. Polyatomic compound consists of:• Ionic compounds polyatomicPolyatomic ionic compounds are compounds polyatomic ions which are the smallest particles. Polyatomic ionic compound composed of cations and anions, namely:1) Compound Salts of polyatomicThe salt compound is a compound salt polyatomic cation or anion is polyatomic ion.2) Basa CompoundAccording to Arrhenius, bases are substances that can release OH-ions in water. Base solution slightly bitter taste and is kausatik (slippery as soap). Basic compounds are ionic compounds consisting of metal cations and anions OH-(except NH4OH). Basic compounds can be formulated as follows.
L: metalOH-: hydroxide (the nature of base)x: valence basa (similar to numbers oxide L)Naming the basic compounds are as follows: alkaline compounds formed by a metal ion yng have sole charge. For example, alkali, alkaline earth metals, and aluminum. Naming compounds are formulated as follows:
base formed by the metal ions have multiple charges, naming compounds are formulated as follows:
• Covalent compounds polyatomicPolyatomic covalent compound is a compound that polyatomic molecule is the smallest particle. The compound belongs to the polyatomic covalent compound is a compound oxyacid.Naming oxyacid compounds are as follows.1) the only non-metallic elements form a compound, the compound ends-at.2) non-metallic element that forms two types of amino acid, which has a lot of oxygen ends-at.3) oxy-halogen acid is an acid that has an acidic oxide and a halogen oxides. In simple terms, means oxyacid halogen atom acid center is the halogen elements. Naming acids halogen oxides depends on the oxidation state or the amount of oxygen.2. Nomenclature of Organic Compoundsa. Simple Hydrocarbon CompoundsHydrocarbon compounds are classified as alkanes, alkenes, and alkynes. The division of these compounds is based on the existence of double bonds in the hydrocarbon compounds.IUPAC nomenclature for alkenes and alkynes compounds based on the nomenclature of alkanes with the number of C atoms corresponding to the change akhirannya match the name of each compound.Comparison of Names Simple Organic CompoundsNumber of atoms C Name Alkanes Alkenes Name Name alkyne1 Methane -2 Ethane Ethene ethyne3 Propane propene Propuna4 Butane Butene ButunaPentane 5 Pentena Pentuna6 Hexane hexene Heksuna7 heptane Heptena Heptuna8 octane octene Oktuna9 Nonana Nonena Nonuna10 decane Dekena Dekunab. Simple Alcohol CompoundsTata nana alcohol compound similar to the nomenclature of simple hydrocarbons. Naming, modest alcohol compounds are as follows.CH3OH: MethanolC2H5OH: EthanolC3H7OH: Propanolc. Organic Acid CompoundsOrganic acids or carboxylic acids by IUPAC called alkanoic acids. General formula is R-COOH. Naming sorted as follows.R (alkyl) is an alkane missing one atom H.B. The law - the law of Basic Chemicals
• LAW OF CONSERVATION OF MASS (Lavoisier LAW)"The mass of substances before and after the reaction is fixed".Example:hydrogen + oxygen = hydrogen oxide(4g) (32g) (36g)
• FIXED COMPARATIVE LAW (LAW Proust)"Comparison of the mass of the elements in each compound is fixed"Example:a. In the compound NH3: N mass: mass of HAr = 1. N: 3 Ar. H= 1 (14): 3 (1) = 14: 3b. On the compound SO3: S mass: mass 0Ar = 1. S: 3 Ar. O= 1 (32): 3 (16) = 32: 48 = 2: 3Advantages of the law Proust:if known mass of a compound or a mass of one of the elements that make up the compound is the mass of other elements could be determined.Example:How many levels of C in 50 grams of CaCO3? (Ar: C = 12; 0 = 16; Ca = 40)Mass C = (Ar C / Mr CaCO3) x mass of CaCO3= 12/100 x 50 grams = 6 gramsmass CLevels of C = mass C / mass x 100% CaCO3= 6/50 x 100% = 12%
Deviations from the law Proust
Please note that while this law is very useful in the fundamentals of modern chemistry, comparative law still does not always apply to all compounds. Compounds that do not comply with this law are called non-stoikiometris compounds. Mass ratio of the elements in the non-stoikiometris compounds vary in different samples. For example, iron oxide wüstite, has a ratio of between 0.83 to 0.95 iron atoms for every oxygen atom. Proust did not know this because of the equipment he uses is not accurate enough to distinguish this figure.
In addition, the law also does not apply to Proust compounds containing different isotopic compositions. Isotopic composition may vary according to the source of the elements that make up the compound. This difference can be used to chemically calendar, because the processes astronomical, atmospheric, and processes in the oceans, Earth's crust and the inside is sometimes have a tendency toward heavy or light isotopes. Caused very little difference, but it can usually be measured with modern equipment. In addition, the law also does not apply Proust in polymers, both natural and artificial polymers polymers.
• LEGAL COMPOUND = COMPARATIVE LAW DALTON"When the two elements can form two or more compounds to the mass of one element as much the second element of the mass ratio in value as integers and simple".Example:If the element nitrogen fertilized den oxygen can be formed,NO where mass N: 0 = 14: 16 = 7: 8NO2 which the mass N: 0 = 14: 32 = 7: 16For the same amount of nitrogen mass ratio of the mass of oxygen in the compound NO: NO2 = 8: 16 = 1: 2
• GAS LAWS To apply the ideal gas equation: PV = nRTwhere:P = gas pressure (atmospheric)V = gas volume (liters)n = moles of gasR = universal gas constant = 0082 lt.atm / mol KelvinT = absolute temperature (Kelvin)The changes of P, V and T from state 1 to state 2 with certain conditions reflected by the following laws:
BOYLE LAW This law is derived from the ideal gas equation of state withn1 = n2 and T1 = T2; thus obtained: P1 V1 = P2 V2LEGAL Gay-Lussac"The volume of gases that react den gas volume of reaction when measured at the same temperature and pressure, will be compared as integers modest den".So for: P1 = P2 and T1 = T2 holds: V1 / V2 = n1 / n2BOYLE LAW-Gay LussacThis law is an extension of the previous law is spoken with the state price den n = n2 to obtain the equation:P1. V1 / T1 = P2. V2 / T2Avogadro's law"At the same temperature and pressure, gases equal volume containing the same number of moles. From this statement it is determined that the state of STP (0o C 1 atm) 1 mole of any gas volume of 22.4 liters of volume is referred to as the molar volume of gas.Example:What volume of 8.5 g of ammonia (NH3) at a temperature of 27o C and a pressure of 1 atm?(Ar: H = 1, N = 14)Answer:85 g of ammonia = 17 mol = 0.5 molThe volume of ammonia (STP) = 0.5 x 4.22 = 2.11 litersAccording to Boyle-Gay Lussac equation:P1. V1 / T1 = P2. V2 / T21 x 112.1 / 273 = 1 x V2 / (273 + 27). V2 = 12:31 litersC. Reaction Equations
Equation has the properties:1) Type of the elements before and after the reaction is always the same2) The number of each atom before and after the reaction is always the same3) Comparison of the reaction coefficient expressed mole ratio (ratio of specific gaseous volume ratio coefficient is also said as long as the same temperature and pressure)Step-by-Step Writing Reaction Equations1) The names of the reactants and reaction products listed. The writing is calledequality predicates.2) Write the equation using the symbols, iechemical formulas of substances, and the form of the reaction. The writing is called equality framework.3) Balance the equation to obtain the equation kerangksequivalent reaction is called chemical equation.Equivalency equationEquivalency equation Raksi lawful immune reaction Lavoisier and Dalton's atomic theory. According to the law of Lavoisier, the chemical reaction does not change the mass. That is, the number and type of atoms on the left (reactants) is equal to the number and type of atoms on the right (the reaction). As per Dalton's atomic theory, chemical reactions no atoms lost or created, all that happened was the rearrangement of the atoms forming reactants new arrangement, the reaction products. To be kind and number of atoms on the left the same as in the right-hand side, the equation equivalent (balanced) by arranging the numbers in front of the reactants and reaction products. Figures given in front of the reactants and reaction products are called coefficients. Number one as coefficient is omitted. Therefore, the equation can be written as follows.Stages equalization equation can be done by:1) Write the equation of the framework, which is not equivalent to the equation, the reactants on the left and the reaction on the right.2) Set the coefficient of the substance / compound is a more elaborate one.3) Balance the reaction by adjusting the coefficients of the reactants and reaction products to another.
D. Mol Concepts
mole is the amount of the chemical unit numbers of the atoms or molecules of Avogadro's number and mass = Mr compound.If Avogadro's number = L then:L = 6.023 x 10231 mole of atoms = L atoms, mass = Ar atom.1 mole of molecules = L = Mr fruits molecular mass of the molecule.The mass of one mole of a substance is called the molar mass of the substanceExample:How many molecules are present in 20 grams of NaOH?Answer:Mr NaOH = 23 + 16 + 1 = 40mol NaOH = mass / Mr = 20/40 = 0.5 molThe number of molecules of NaOH = 0.5 L = 0.5 x 6023 x 1023 = 3.01 x 1023 molecules.Mol relationship with the number of particlesIt is known that substances 1mol X = l fruit particles of matter X, then2 moles of substance X = 2 x L particles of substance X5 moles of substance X = 5 x L particles of substance Xn moles of substance X = n x L particles of substance XThe number of particles = n x L
Future Atom and The Formula1) Atomic MassAtomic mass is defined as the mass of an atom in atomic units of mass units (amu) or atomic mass units (sma). One amu is defined as 1/12 times the mass of one atom of C-12. Carbon-12 is one isotope of carbon has 6 protons and 6 neutrons. This element is used as a standard of comparison for these elements have properties that are very stable with long half-lives. By setting an atomic mass of 12 C-12 sma, we can determine the mass of atoms of other elements. For example, it is known that the hydrogen atom has a mass of only 8.4% of the mass of one atom of C-12. Thus, the mass of a hydrogen atom is 8.4% or 1.008 x 12 sma sma. By similar calculations, one can obtain the mass of the oxygen atom is 16.00 sma and an atomic mass of iron is 55.85 sma. This means that a single iron atom has a mass about 56 times the mass of a hydrogen atom.2) Relative Atomic Mass (Ar)Atomic mass of the element of truth can not be measured by weighing the mass of atoms, because atoms are so small. Atomic mass of the element is determined by comparing the average atomic mass of the element to 1/12 the average mass of one atom of carbon-12 so obtained is the atomic mass relative atomic mass (Ar).3) Relative Molecular MassElements and compounds in the form of molecular particle, its mass is expressed in relative molecular mass (Mr). Basically the relative molecular mass (Mr) is the ratio of the average mass of a single molecule of an element or compound with 1/12 the average mass of one atom of carbon-12.
So many types of molecules, so no table relative molecular mass. However, the relative molecular mass can be calculated by adding the relative atomic mass of the atoms that form the molecule.Mr = ΣArTo compound the particle is not shaped molecules, but pair ions, such as NaCl then Mr. compound called relative formula mass. Relative formula mass is calculated in the same way as the calculation of the relative molecular mass, ie by adding the relative atomic mass of the elements in the formula of the compound.4) Molar MassIt is known that a mole is the amount of substance containing particles (atoms, molecules, ions) as there are atoms in 12 grams of carbon with mass number 12 (carbon-12, C-12). So it looks that the mass of one mole of C-12 is 12 grams. The mass of one mole of a substance is called the molar mass. Molar mass equal to the relative molecular mass (Mr) or relative atomic mass (Ar) of a substance expressed in grams.Molar Mass = Mr or Ar a substance (g)
5) Molar VolumeAvogadro get the results of experiments that at a temperature of 0 ° C (273 K) and a pressure of 1 atmosphere (76cmHg) got exactly 1 liter of oxygen to the mass of 1.3286 grams.
Selasa, 09 Oktober 2012
ATOM, ION AND MOLECULES (CH 2)
Understanding
Atom
Atom is the smallest part of an element that still has the properties of that element. Each atom of an element have different properties to the atomic nature of the other elements.
Atom is the smallest part of an element that still has the properties of that element. Each atom of an element have different properties to the atomic nature of the other elements.
Development of Atomic Theory
- In 400 BC Democritus and Leucippus states that all matter is composed by particles are very small and can not be divided again. And then they named the atom with greek (atomos: a = no, Tomos = cut or split). Whereas Aristotle states that matter is continuous, meaning that the material can be split or shared continuously without limit.
- In 1803 John Dalton (1766-1844) Atomic Model Dalton à states:
· The material is composed of small particles tidakdapat divided again,
· Atoms of the same (an element) has the same properties
· Atoms can join together chemically to form moleku
Weaknesses: does not explain the difference between atomic elements with other atoms
- In 1898 JJ Thomson (1856-1940) stated à Thomson Atomic Model:
· Atomic incandescent spherical positively charged and contains a number of electrons in the negatively charged atoms
· The number of positive and negative charges the same, so the charge is neutral atoms
- In 1911 Ernest Rutherford (1887-1931) Model àmenyatakan Rutherford:
· Atomic nucleus contains positively charged atom in the center and surrounded by negatively charged electrons
Weakness: not able to explain why the electrons do not fall into the nucleus due to the gravity of the core electrons
- Niels Bohr Model à states
· Electrons can spin only through a particular trajectory
· If the electron perpindah kelintasan deeper, it will be emitted energy whereas when you go out it will be absorbed energy
Weaknesses: can not explain the spectrum of colors from many electron atoms.
- Erwin Schrodinger and Warner Heisenbreg (1925-1926) stated à-Heisenbreg Schrodinger Atomic Model: electrons can be determined only possible where it is, which is located in a space called the electron cloud.
- In 400 BC Democritus and Leucippus states that all matter is composed by particles are very small and can not be divided again. And then they named the atom with greek (atomos: a = no, Tomos = cut or split). Whereas Aristotle states that matter is continuous, meaning that the material can be split or shared continuously without limit.
- In 1803 John Dalton (1766-1844) Atomic Model Dalton à states:
· The material is composed of small particles tidakdapat divided again,
· Atoms of the same (an element) has the same properties
· Atoms can join together chemically to form moleku
Weaknesses: does not explain the difference between atomic elements with other atoms
- In 1898 JJ Thomson (1856-1940) stated à Thomson Atomic Model:
· Atomic incandescent spherical positively charged and contains a number of electrons in the negatively charged atoms
· The number of positive and negative charges the same, so the charge is neutral atoms
- In 1911 Ernest Rutherford (1887-1931) Model àmenyatakan Rutherford:
· Atomic nucleus contains positively charged atom in the center and surrounded by negatively charged electrons
Weakness: not able to explain why the electrons do not fall into the nucleus due to the gravity of the core electrons
- Niels Bohr Model à states
· Electrons can spin only through a particular trajectory
· If the electron perpindah kelintasan deeper, it will be emitted energy whereas when you go out it will be absorbed energy
Weaknesses: can not explain the spectrum of colors from many electron atoms.
- Erwin Schrodinger and Warner Heisenbreg (1925-1926) stated à-Heisenbreg Schrodinger Atomic Model: electrons can be determined only possible where it is, which is located in a space called the electron cloud.
Atomic Structure
Ø atomic model that can be used to study the atomic structure is Rutherford and Bohr model of the atom.
Ø Bohr's atomic model is similar to the position of the sun to the planets in the solar system. The mass of the nucleus is much larger than the electron mass. Therefore, the electrons surrounding the nucleus.
- Atoms consist of a nucleus and electrons. The nucleus is composed of protons and neutrons.
- Protons are positively charged (+), uncharged neutrons (neutral), while the electrons are negatively charged (-). Same number of electrons and protons, so the atom becomes neutral charge.
- The number of protons and electrons are expressed as atomic number, number of protons and neutrons is expressed as the mass of the atom. Arrangement of atoms can be written using the following notations:
Rounded Rectangle: (_ ^ A) X_z ^ Description:
X = symbol element
A = atomic mass = number of protons + number of neutrons
Z = atomic number = number of protons = number of electrons
A-Z = Number of neutrons
Ø atomic model that can be used to study the atomic structure is Rutherford and Bohr model of the atom.
Ø Bohr's atomic model is similar to the position of the sun to the planets in the solar system. The mass of the nucleus is much larger than the electron mass. Therefore, the electrons surrounding the nucleus.
- Atoms consist of a nucleus and electrons. The nucleus is composed of protons and neutrons.
- Protons are positively charged (+), uncharged neutrons (neutral), while the electrons are negatively charged (-). Same number of electrons and protons, so the atom becomes neutral charge.
- The number of protons and electrons are expressed as atomic number, number of protons and neutrons is expressed as the mass of the atom. Arrangement of atoms can be written using the following notations:
Rounded Rectangle: (_ ^ A) X_z ^ Description:
X = symbol element
A = atomic mass = number of protons + number of neutrons
Z = atomic number = number of protons = number of electrons
A-Z = Number of neutrons
Electron Configuration
- Electrons surround the nucleus of an atom on the trajectories (shells) with a certain energy level. The arrangement of electrons in an atom is called the electron configuration shell.
- The number of electrons that can be accommodated masimum each skin is 2N2 where n is the number of skin. For the first 20 elements of the outer shell is not more than 8 electrons, for example, potassium has 19 electrons and its configuration is not 2 8 8 1 2 8 9.
Ø Ion
ü Ions are electrically charged particles that are formed when an atom loses an electron or or more to form a stable outer shell. Ion that lost an electron positively charged (cations) and the capture of an electron is negatively charged (anionic).
ü event release or influx of ions is called ionization. Ion was first discovered by the German physicist, Julius Elster and Hans Friedrich Geitel in 1899.
ü Proton is located in the nucleus of an atom that prtoton hard to get out of the atom. To remove the proton required enormous energy (nuclear reaction). Electrons are outside the nucleus (around the nucleus of an atom in a particular orbit) so that the electrons can leave a an atom. Furthermore, the electron is accepted by the other atom. In other words, an atom can release or accept electrons.
- Electrons surround the nucleus of an atom on the trajectories (shells) with a certain energy level. The arrangement of electrons in an atom is called the electron configuration shell.
- The number of electrons that can be accommodated masimum each skin is 2N2 where n is the number of skin. For the first 20 elements of the outer shell is not more than 8 electrons, for example, potassium has 19 electrons and its configuration is not 2 8 8 1 2 8 9.
Ø Ion
ü Ions are electrically charged particles that are formed when an atom loses an electron or or more to form a stable outer shell. Ion that lost an electron positively charged (cations) and the capture of an electron is negatively charged (anionic).
ü event release or influx of ions is called ionization. Ion was first discovered by the German physicist, Julius Elster and Hans Friedrich Geitel in 1899.
ü Proton is located in the nucleus of an atom that prtoton hard to get out of the atom. To remove the proton required enormous energy (nuclear reaction). Electrons are outside the nucleus (around the nucleus of an atom in a particular orbit) so that the electrons can leave a an atom. Furthermore, the electron is accepted by the other atom. In other words, an atom can release or accept electrons.
The valence electrons:
- Establishment of positive ions à atom loses electrons
- The formation of negative ions capture electrons à atom
- Ionikàsenyawa compound formed from positive ions and negative ions bond together to form a neutral compound. Ionic compounds have a high melting point. That's because the compound there is a very strong bond between the ions forming
Ø Molecular
ü The molecule is the smallest part of a compound and still have the properties of these compounds. In other words, the molecule is a combination of two or more atoms chemically.
ü Based on the types of atoms that make up molecules, molecules are divided into two, namely:
- Molecular Elements à bunch of atoms of the same element chemically combine to form a molecule. In other words, the molecule consists of only one type of constituent atoms.
The molecule can be divided into two elements, namely:
· Molecular diatomikàmolekul element composed of two atoms of the same. Example: H2 (hydrogen), O2 (oxygen gas)
· Molecular poliatomikà molecular elements composed of more than two of the same atom. Example: P4, S8
Examples of elements of hydrogen formation
ü Each hydrogen atom has satuelektron
ü electrons are trying to form a stable electron configuration, ie two (the maximum number of electrons on the skin to-1)
ü The two electrons have enough power to attract each other
ü The atoms used by two atoms (sharing)
ü Each nucleus has two electrons in the atomic shell.
Covalent bond
ü bonds are bonds that form due to the use of electrons together
ü Iakatan covalent ionic bond is less powerful than
ü If there is 1 atom pairs are used together, it is called a single covalent bond
ü If there are 2 pairs of atoms that are used together, it is called a double covalent bond
ü The electrons are not shared are called nonbonding electrons (bonding = bond)
ü covalent Senayawa not conduct electricity because it does not form ions are electrically charged.
- Molecular compounds à compounds composed of more than one type of constituent atoms.
Example: H2O (water), CO2 (carbon dioxide)
Examples formation of water molecules
ü The water molecule consists of two atoms of H and 1 atom O
ü Atomic H has 1 electron in its outer shell
ü Atom O has 6 electrons in its outer shell
ü Each H atom to one electron eletron by pulling 2 of 2 atoms O
ü Atom O requires two atoms. The trick is to draw two electrons of two atoms H
ü There are two covalent bonds.
Ø Atoms, Ions, Molecules in Daily Chemical Products
ü Breathing a breath of air molecules udaramengandung elements such as oxygen (O2), nitrogen (N2), and the molecules of compounds such as carbon dioxide (CO2) emissions.
ü The sweetness of sugar molecules composed of sugar or sucrose (C12H22O11).
ü taste sour pickles, a few drops of vinegar derived from molecules containing vinegar (CH3COOH).
ü kitchen salt derived from a chemical compound that is NaCl, which if dilarut in water into ions Na + and Cl-
ü Gasoline or diesel fuel composed of hydrocarbon molecules
ü Glass, glasses, plates consist of molecules of silica oxide (SiO2)
ü plastic polymers include polyethylene, polypropylene, polyurethane, and PVC
ü polymer is polyisoprene rubber and polystyrene.
- Establishment of positive ions à atom loses electrons
- The formation of negative ions capture electrons à atom
- Ionikàsenyawa compound formed from positive ions and negative ions bond together to form a neutral compound. Ionic compounds have a high melting point. That's because the compound there is a very strong bond between the ions forming
Ø Molecular
ü The molecule is the smallest part of a compound and still have the properties of these compounds. In other words, the molecule is a combination of two or more atoms chemically.
ü Based on the types of atoms that make up molecules, molecules are divided into two, namely:
- Molecular Elements à bunch of atoms of the same element chemically combine to form a molecule. In other words, the molecule consists of only one type of constituent atoms.
The molecule can be divided into two elements, namely:
· Molecular diatomikàmolekul element composed of two atoms of the same. Example: H2 (hydrogen), O2 (oxygen gas)
· Molecular poliatomikà molecular elements composed of more than two of the same atom. Example: P4, S8
Examples of elements of hydrogen formation
ü Each hydrogen atom has satuelektron
ü electrons are trying to form a stable electron configuration, ie two (the maximum number of electrons on the skin to-1)
ü The two electrons have enough power to attract each other
ü The atoms used by two atoms (sharing)
ü Each nucleus has two electrons in the atomic shell.
Covalent bond
ü bonds are bonds that form due to the use of electrons together
ü Iakatan covalent ionic bond is less powerful than
ü If there is 1 atom pairs are used together, it is called a single covalent bond
ü If there are 2 pairs of atoms that are used together, it is called a double covalent bond
ü The electrons are not shared are called nonbonding electrons (bonding = bond)
ü covalent Senayawa not conduct electricity because it does not form ions are electrically charged.
- Molecular compounds à compounds composed of more than one type of constituent atoms.
Example: H2O (water), CO2 (carbon dioxide)
Examples formation of water molecules
ü The water molecule consists of two atoms of H and 1 atom O
ü Atomic H has 1 electron in its outer shell
ü Atom O has 6 electrons in its outer shell
ü Each H atom to one electron eletron by pulling 2 of 2 atoms O
ü Atom O requires two atoms. The trick is to draw two electrons of two atoms H
ü There are two covalent bonds.
Ø Atoms, Ions, Molecules in Daily Chemical Products
ü Breathing a breath of air molecules udaramengandung elements such as oxygen (O2), nitrogen (N2), and the molecules of compounds such as carbon dioxide (CO2) emissions.
ü The sweetness of sugar molecules composed of sugar or sucrose (C12H22O11).
ü taste sour pickles, a few drops of vinegar derived from molecules containing vinegar (CH3COOH).
ü kitchen salt derived from a chemical compound that is NaCl, which if dilarut in water into ions Na + and Cl-
ü Gasoline or diesel fuel composed of hydrocarbon molecules
ü Glass, glasses, plates consist of molecules of silica oxide (SiO2)
ü plastic polymers include polyethylene, polypropylene, polyurethane, and PVC
ü polymer is polyisoprene rubber and polystyrene.
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