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Chemistry The
central science Chemistry is the study of matter including their chemical and physical properties chemical and physical changes it undergoes energy changes that accompany those processes
GENERAL CHEMISTRY Rowel P. Catchillar, MS Phar
Chemistry: the central science
Major Divisions
energy
Laws
General Chemistry
Inorganic Chemistry
Physical Chemistry
Organic Chemistry
changes
Principles
Study of matter composition
properties
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Major Divisions Anything Anything
that occupies space and has mass
Analytical Chemistry
Biochemistry
Nuclear Chemistry
Geological Chemistry
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Mass & Weight
Mass vs Weight
Mass
refers to the amount of matter present in the material is a measure of how much matter something contains
Weight
the measure of the earth’s gravitational attraction of an object ; mass x gravitational attraction is a measure of how strongly gravity pulls downwards
Units of Measurement
States of Matter
STATE SHAPE
Metric System or SI is a decimal system of units for measurements measurements of mass, length, time and other physical quantities Quantity Length Mass Time Temperature Amount of substance Electric current Luminous intensity
Name of Unit Meter Kilogram Seconds Kelvin Mole Ampere Candela
Interconversion of Matter
VOLUME
Solid Definite Definite Liquid Indefinite Definite Gas Indefinite Indefinite
COMPRESSION Very slight Slight High
Symbol m kg sec K mol A cd
IFA Strongest Strong Weakest
MOLECULAR MOTION Vibration Gliding Constant random motion
Classification of Matter Element
Simplest form of matter,1 kind of material or atom
Compound
Substance composed of two or more elements united chemically in definite proportion
Mixture
Composed of 2 or more substances that are not chemically combined
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Classification of Mixture
Classification of Mixture
Based
Based
on Nature of Particles
HETEROGENEOUS
HOMOGENEOUS
Consists of physically Consists of uniform distinct parts, each with properties throughout different properties given samples; two or more substance but single phase
Eg: Sand and water mixture NaCl dissolved in water
on Particle Size
Solution – uniform mixture, composed of solute and solvent Suspension – aka Coarse mixture, finely divided solid materials distributed in a liquid Colloid – particles of solute are not broken down to the size of the molecules but are small enough to remain suspended and evenly dispersed throughout the medium
Separation of Mixture
Separation of Mixture
Decantation
Evaporation
Difference in specific gravity
Distillation
Distillation followed by condensation
escape of molecules from the liquid state to gaseous/vapor state
Magnetic
separation
metals
Separation of Mixture
Separation of Mixture
Filtration
Fractional crystallization
use of filter paper
Sorting
mechanical separation
Centrifugation
to increase settling of a precipitate
lowering the temperature so that the more insoluble component crystallizes first Based on the difference in solubility Chromatography
difference in solvent affinity
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Properties of Matter
Properties of Matter
Extrinsic
Intrinsic
or extensive properties
qualities that are not characteristic of the substance itself; those that depend on the amount or quantity of materials present Eg: weight, volume, pressure, heat content
Changes in matter
Physical change
Chemical change
Change in phase, no new substance is formed Change in both intrinsic and extrinsic properties; new substance is formed
Nuclear Change
Change in the structure, properties, composition of the nucleus of an atom resulting in the transmutation of the element into another element. Nuclear Nuclear
fission - splitting of a heavy atom fusion- union of 2 light atoms to form a bigger molecule
or Intensive properties
qualities that are characteristic of any sample of a substance regardless of the shape or size of the sample; those that depend on the quality or kind of material that: Cannot
be measured (taste, color and odor) Measurable (melting point, boiling point, density, specific gravity)
Evidences of chemical change Evolution
of gas Formation of a precipitate Emission of light Generation of electricity Production of mechanical energy Absorption/liberation of heat
Processes involved in chemical change
Processes involved in chemical change
Oxidation
Neutralization
LEORA Oxidation (+) Oxygen Dehydogenation (-) Hydrogen Reduction
GEROA Hydrogenation (+) Hydrogen Reduction (-) Oxygen
Salt formation
Hydrolysis
Breakdown of molecule in the presence of water
Saponification
Soap formation
Fermentation Alcohol +
CO2
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Laws Governing Matter & Energy
Laws Governing Matter & Energy
Law of mass action the rate of the reaction is proportional to the product of the concentrate of the reactants to the power of its coefficient in a balanced equation
Law
aA
+ bB
of Mass Action
cC + dD
Laws Governing Matter & Energy
Laws Governing Matter & Energy
Law
Law
of Mass Action
of Mass Action
Laws Governing Matter & Energy
Laws Governing Matter & Energy
Result Analysis
Law
K >> 1, products favored K << 1, reactants favored
of Conservation of Energy energy can neither be created nor destroyed, but it can be transformed from one form to another
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Laws Governing Matter & Energy
Laws Governing Matter & Energy
Law
Law
of conservation of mass
no change is observed in the total mass of the substances involved in a chemical reaction
Laws Governing Matter & Energy Law
of Constant Composition
Law of Definite Proportion Proust’s Law States that: “in a pure compound, the elements are always present in the same proportion by mass” Example: H2O
ATOMS, MOLECULES & IONS
of Multiple Proportion
atoms of two or more elements may combine in different ratios to produce more than one compound
ATOMS MOLECULES IONS
ATOMS, MOLECULES & IONS
Discovery of Atoms & Atomic Models
ATOMS
Democritus
smallest particle of an element
MOLECULE
smallest unit of a compound
ION
positively or negatively charged atom Positive ion: cation Negative
ion: anion
Matter is made up of indivisible particles he pounded up materials in his pestle and mortar until he had reduced them to smaller and smaller particles which he called ATOMOS (indivisible)
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Discovery of Atoms & Atomic Models John
Dalton
Dalton
proposed a modern atomic model based on experimentation not on pure reason All matter is made of atoms. Atoms of an element are identical. Each element has different atoms. Atoms of different elements combine
constant ratios to form compounds. are rearranged in reactions.
in
Atoms
His ideas account for the law of conservation of mass and the law of constant composition.
Model: “Billiard Ball Model”
Discovery of Atoms & Atomic Models J.J.
Thomson
Raisin Bread / Plum Pudding Model (Negative electrons in a positive framework) found that atoms could sometimes eject a far smaller negative particle which he called an electron
Discovery of Atoms & Atomic Models
Discovery of Atoms & Atomic Models
Ernest
Gold
Rutherford
Gold film experiment (99% passed; <1% deflected) Proposal: Atom
is mostly an empty space (99% passed) Most of its and (+) particles are concentrated in the nucleus (<1% deflected)
Discovery of Atoms & Atomic Models Neil
Film Experiment Most
particles passed through. So, atoms are mostly empty. Some positive particles deflected or bounced back! Thus, a “nucleus” is positive & holds most of an atom’s mass
Planetary Model
Bohr
Refined Rutherford’s idea by adding that the electrons were in orbits (like planets orbiting the sun) Model: “Planetary Model”
electrons in orbits
nucleus
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Discovery of Atoms & Atomic Models
Discovery of Atoms & Atomic Models
James
Erwin
Chadwick
“Neutron” discovery
Schrodinger
Quantum Mechanical Model
Atomic Structure
Nuclide Writing
Composition
A
Nucleus & electron cloud
Atomic
Particles
Proton Neutron Electron
nuclide is an atom characterized by a definite atomic number and mass number
1,836
lighter than proton, thus negligible
Remember Me!
Exercises
If
Determine
neutral
Atomic
If
# = Proton = Electron
charged (cation or anion):
Atomic
# = Proton (but not equal to electron)
the
Proton Atomic # Neutron Electron Mass Number Nucleon #
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Exercises Determine
Exercises the
Proton Atomic # Neutron Electron Mass Number Nucleon #
Essential Terms
Determine
the
Proton Atomic # Neutron Electron Mass Number Nucleon #
Identify whether the following pairs are: isotopes, isobars or isotones
Isotopes Isobars Isotones
Identify whether the following pairs are: isotopes, isobars or isotones
Identify whether the following pairs are: isotopes, isobars or isotones
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Identify whether the following pairs are: isotopes, isobars or isotones
Allotropism phenomenon
of an element existing in two or more physical forms Same elemental constituent, different form
Electron Configuration representation
of the arrangement of electrons that are distributed among the orbitals.
Long-hand
Method
Diagonal rule Madelung’s rule Klechkowski’s rule “An
empirical rule for determining the order in which atomic orbitals are filled”
Short-hand
notation
Nobel gas method
Orbital
Notation
Electronic Principles
Quantum Mechanics
Heisenberg’s
Principal
Uncertainty
Theory Pauli’s Exclusion Theory Aufbau Principle Diagonal rule Hund’s Rule
quantum number
Determines the main energy level and the size Symbol: n Values: positive integer (1,2,3,4…)
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Quantum Mechanics
Quantum Mechanics
Azimuthal
Magnetic
QN / Angular Momentum Number
Determines the shape and subshell/sublevel Shapes: s = spherical p = dumbbell-shaped d = cloverleaf f = too complex
QN
Describes the spatial orientation Symbol: m or ml values: -l to +l
Symbol: l Values: 0 to (n-1)
Quantum Mechanics
Quantum Number Determination
Spin
3p4
QN
Determines the spin/rotation Values: +1/2 (clockwise) or -1/2 (counterclockwise)
4s2 3d10
The Periodic Table of Elements
The Periodic Table of Elements
Antoine
Johann Dobereiner Triads; According to physical properties middle element of a triad was nearly equal to the arithmetic mean of atomic masses of other two elements
Lavoisier
wrote the first extensive list of elements - containing 33 elements
Element Lithium Sodium Potassium
Atomic mass 7 23 39
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The Periodic Table of Elements John
The Periodic Table of Elements
Alexander Newland
Octaves "every eighth element had properties similar to the first element”
Li Be (6.9) (9.0) Na Mg (23.0) (24.3) K Ca
B C (10.8) (12.0) Al Si (27.0) (28.1)
N (14.0) P (31.0)
O (16.0) S (32.1)
F (19.0) Cl (35.5)
(39.1) (40.1)
The Periodic Table of Elements
The Periodic Table of Elements
Meyer
Henry
and Mendeleev
Physical and chemical properties are periodic function of their atomic weights
Moseley
Elements are arranged based on atomic numbers Modern periodic table
Parts of Periodic Table
Parts of Periodic Table
Period
Groups
1st shortest period 2nd and 3 rd short period, 8 elements 4th and 5 th long periods, 18 elements each 6th period: Lanthanide series (rare earth elements), 14 elements 7th period: Actinide series, 14 elements
There are 18 groups in a periodic table The groups are divided into A and B groups Group IA to VIIIA has all the normal (representative elements) Group IB to VIIIB holds all the transition metal elements
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The Periodic Table
Metals vs Nonmetals
The
modern periodic table is approximately divided into metals and non-metals
Metallic elements – left-hand side Nonmetals – right-hand side Inert gas – extreme right hand side Transition metals – bridged between highly metallic alkali elements and the non-metals lie on the center of the table Lanthanide and actinide series – kept separately
METALS Good conductors of heat and electricity Form BASIC oxides Lustrous, Ductile, Malleable High Density High Melting point Tends to lose e-
Metalloids
Periodic Trends
Intermediate between metals
Atomic
& non-metals Si, Ge, Po, Sb, As, Te, B
Electron affinity
NON-METALS Poor conductors Form ACIDIC oxides Dull & Brittle if Solid Low Density Low Melting point Tends to accept e-
Radius
½ the distance between 2 nuclei amount of energy released when an atom gains an electron ; property to accept an electron
Electronegativity Ability
to attract electrons in itself
Ionization
energy or potential
energy required to remove an electron from a neutral atom
Periodic Trends
Types of Chemical Bonding
ATOMIC
Intramolecular
SIZE / METALLIC PROPERTY / ATOMIC RADIUS
Right Left :: INCREASE Top Bottom :: INCREASE
ELECTRONEGATIVITY
/ IE / EA
From Left to Right INCREASE From Bottom to Top INCREASE
For,
ION SIZE:
Force of
Attraction
Covalent Bond Polar
Covalent Bond Non-polar
Ionic Bond
Atom
to CATION :: decrease in ion size Atom to ANION :: INCREASE in ion size
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Covalent or Ionic Bond?
Memorize me!
Basis:
electronegativity differences
>1.7 ionic 0.5-1.7 polar covalent <0.5 non-polar covalent Based
on elemental attribute
Metal + Nonmetal ionic 2 Nonmetals covalent
Element
Electronegativity
Fluorine
4.0
Oxygen
3.5
Chlorine
3.0
Nitrogen
3.0
Bromine
2.8
Carbon
2.5
Sulfur
2.5
Hydrogen
2.1
Sodium
0.9
Potassium
0.8
Force of attraction: Ionic or covalent?
Chemical Bonding
Based
The
on Electronegativity Difference SrCl2 PCl3 NH3 RbBr LiCl
Ionic Covalent Covalent Ionic Ionic
Lewis Dot Diagrams
Get the sum of valence electron present in a formula. Draw trial structure (single bonds only) Get the difference of valence electrons & electrons of single bonds Incorporate the missing electrons in the structure. Be sure to satisfy octet rule! Last resort: if octet rule is not satisfied, indicate double or triple bonds
Chemical Bonding
SOLUTIONS
Write
Solution
the Lewis Diagram of the following:
Water CH3F Br 2 NH3 CH2O C2H2
is a homogeneous (or uniform) mixture of two or more substances. Composition:
The solute is a compound of a solution that is present in lesser quantity than the solvent The solvent is the solution component present in the largest quantity.
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Types of Solutions
Factors affecting solubility
Based
The
on the solubility of the solution
Saturated Unsaturated Supersaturated
magnitude of difference between polarity of solute and solvent
The greater the difference, the less soluble is the solute.
Nature
of solute and solvent
“Like dissolves like”
Factors affecting solubility
Factors affecting solubility
Temperature
Pressure – affects
increase in temperature usually increases solubility Exothermic Solubility
decreases with increase
in temp.
Endothermic solubility
increases with increases in temperature
Factors affecting solubility Presence
of Salts
Salting-out – presence of salt decreases solubility Salting-in – Presence of salt increases solubility
gases only
Henry’s Law - the solubility of a gas increases as pressure increases
Particle
size & Surface area
Decreases particle size increase solubility Increased SA increased solubility
Concentration-Dependent Solution Properties “Raoult’s law”
…”when a solute is added to a solvent, the vapor pressure of the solvent decreases in proportion to the concentration of the solute”
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Colligative Properties
Colligative Properties
Colligative properties are
Vapor pressure lowering
solution properties that depend on the concentration of the solute particles, rather than the identity of the solute.
addition of non-volatile solute lowers the vapour pressure of the liquid
Colligative Properties
Colligative Properties
Freezing
Boiling
point depression
presence of salt/non-volatile solid will cause lowering of freezing point Application: Manufacture of ice cream
BP is the equilibrium between the liquid and the gas VP=AP
Colligative Properties
Gas Laws
Osmotic pressure
Kinetic
Osmosis is the movement of solvent from a dilute solution to a more concentrated solution through a semipermeable membrane. osmotic pressure applied pressure to stop the movement of solvent
Clinical Correlation:
Isotonicity Hypertonic Hypotonic
point elevation
gases
molecular theory of
Gases are made up of small atoms or molecules that are in constant, random motion The distance of separation among these atoms or molecules is very large in comparison to the size of the individual atoms or molecules.
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Gas Laws
Gas Laws
Kinetic molecular theory of gases
All of the atoms and molecules behav e independently. No attractive or repulsive forces exist between atoms or molecules in a gas. Atoms and molecules collide with each other and with the walls of the container without losing energy. The energy is transferred from one atom or molecule to another. The average kinetic energy of the atoms or molecules increases or decreases in proportion to absolute temperature.
Boyle’s
Gas Laws Boyle’s
Law
Sometimes: Mariotte law Relationship of pressure and volume at constant temperature Inversely proportional P1V1 = P2V2 (show derivation) P 1/V
Gas Laws Law
Charles’
Law
Relationship of volume and temperature at constant pressure Directly proportional V T Formula:
Gas Laws Charles’
Gas Laws Law
Gay-Lussac’s Law
Relationship of temperature and pressure at constant volume Directly proportional (⬆ temperature, ⬆ pressure) Formula:
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Gas Laws
Gas Laws
Combined
Gas Law
Provides convenient expression for performing gas law calculations involving the most common variables: pressure, volume, and temperature.
Ideal
Gas Law (Ideal Gas Equation) Formula: PV = nRT Where: R
= gas constant (R = 0.08206 L-atm / molK) T = (Kelvin instead of degrees Celsius) n = moles
Formula:
STP: T
= 273.15 K = 1 atm V = 22.4 L P
Gas Laws
Gas Laws
Real
Dalton’s
Gas Equation
Van der Waal’s Equation Formula: Where:
accounts for the intermolecular attractive forces;
accounts for the incompressibility of the molecules.
Gas Laws Graham’s
Law of Partial Pressure
Total pressure is equal to the sum of partial pressure of each gas Pt = P1 + P2 + P3 + … If each gas obeys the ideal-gas equation, then:
Gas Laws Law
States that the rate of diffusion of the gas and the speed of the gas molecules are inversely proportional to the square root of their density
Avogadro’s
Law
Gases of equal volumes at the same temperature and pressure contain the same number of molecules. volume of a gas maintained at constant temperature and pressure is directly proportional to the number of moles of the gas Formula:
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Acids & Bases
Acids & Bases
D i s s o c i a t i o n
Electrolytes:
substances whose aqueous solution conduct electricity such as acids, bases and salts
separation of salt ions
I o n i z a t i o n
acids and bases, most salts; complete dissolution
formation of ions
Weak electrolytes weak
acid/ weak bases; incomplete dissolution; slight dissociation
**These terms are often used interchangeably to describe the processes taking place in water.
Acid-Base Theories
Strong electrolytes strong
Non-electrolytes: do not conduct electricity
General Properties of Acids Taste: SOUR Litmus : blue red Aqueous solutions conduct electricity Reacts with metal to liberate hydrogen gas Reacts with carbonate and bicarbonate to produce carbon dioxide Turns colorless with phenolphthalein Turns red with methyl orange indicator Most common strong acids: HCl, HBr, HI, HNO3, HCIO3, HCIO4, H2SO4
THEORY ACID BASE Arrhenius Substance that yields Substance that Theory H+ or H3O+ in H2O yields OH- in H2O BronstedProton donor Proton acceptor Lowry Theory Lewis Theory Electron-acceptor Electron donor Pearson’s Hard acids are electron acceptor with high HSAB positive charges and relatively small sizes while soft acids have positive charges and relatively large sizes
General Properties of Bases
pH
Taste:
measure
BITTER Litmus: red blue Aqueous solutions conduct electricity Slippery to touch Pink color with phenolphthalein Yellow with methyl orange Most common strong bases NaOH, KOH, Ca(OH)2
of acidity or basicity of a substance range: Sorensen scale (0-14) pH = 7; pH < 7; pH > 7 alkalinity, increase in number acidity, in number
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Dissociation Constant
Dissociation Constants
measures
Acid
the propensity of a larger object to separate (dissociate) reversibly into smaller components
(Ka)
Formula: pKa = -log Ka
Base
(Kb)
Dissociation Constant Dissociation Constant
Formula: pKb = -log Kb
Dissociation
Fomula: pKw = pH + pOH
Essential Formula
Salts
pH = -log (H+) WA: pH = -log ( . ) SB: pH = pkw – [(-log (OH-)] WB: pH = pkw – [(-log .)
SA
SA:
Note
Ka or Kb > 10 O is strong acid/base Ka or Kb <10 O is weak acid/base
contant of water
+ SB
neutral salt (pH =
7) SA+ WB acidic salt (pH < 7) WA + SB basic salt (pH >7) Weak acid + Weak base pH = + −
Buffer Equation
Nomenclature & Formula Writing
Henderson-Hasselbalch
Rule
Equation
of Inorganic Compound
“…an inorganic compound is produced by simple attraction of (+) & (-) particles
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Nomenclature & Formula Writing ionic : metal + nonmetal (formation of one, two or more cations)
Binary Ionic
Binary
Binary ionic with one type of cation formed Common metals; monovalent metal + nonmetal Name the metal. Add stem (-ide)
Binary Ionic Binary
ionic with two or more types of cations
FORMULA AlCl3
NAME
Al2O3
FORMULA
NAME Barium sulfide
LiI MgBr 2
Calcium carbide HCl
Sodium hydride
HI
Na2O
Binary Ionic FORMULA
Cu+1 Cu+2 Hg+1; (Hg2)+2 Hg+2 Fe+2 Fe+3 Sn+2 Sn+4 Pb+2 Pb+4 As+3 As+5 Ti+3 Ti+4
STOCK SYSTEM NAME Copper (I) Copper (II) Mercury (I)
CLASSICAL NAME
Mercury (II) Iron (II) Iron (III) Tin (II) Tin (IV) Lead (II) Lead (IV) Arsenic (III) Arsenic (V) Titanium (III) Titanium (IV)
Nomenclature & Formula Writing
FORMULA SnF4 Fe2O3 PBI2 CuO
NAME
FORMULA
NAME Iron (II) sulfide Cuprous oxide Stannous chloride Titanic bromide
Binary Molecular
Binary
molecular: non-metal + non-metal
Name the first element using a prefix if more than one atom of this element. If atom is one, DO NOT USE –mono prefix (just name the element) Write stem name + (-ide). USE PREFIX TO INDICATE NUMBER OF ATOMS Prefixes: -mono; -di; -tri; -tetra; -penta; -hexa; -hepta; -octa; -nona; -deca
FORMULA CO CO2 PCl3 CCl4 N2O
NAME
FORMULA H2O N2O4 NO S2Cl2 Cl2O
NAME
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Nomenclature & Formula Writing Ternary
ionic: metal + polyatomic ion
Naming: Write the name of the cation and anion
Ternary Ionic: Memorize me! NAME Borate Bromate Carbonate Perchlorate Chlorate Chlorite Hypochlorite
FORMULA CHARGE BO33-3 BrO3-1 CO32-2 ClO4 ClO3-1 ClO2ClO-
Ternary Ionic: Memorize me! NAME Oxalate Permanganate Phosphate Sulfate Sulfite
FORMULA CHARGE C2O42-2 MnO4 -1 3PO4 -3 2SO4 -2 2SO3 -2
Ternary Ionic: Memorize me! NAME Acetate Ammonium Arsenate Hydrogen carbonate or bicarbonate Hydrogen sulfate or bisulfate
FORMULA CHARGE C2H2O2-1 + NH4 +1 3 AsO4 -3 HCO3 -1 HSO4-
-1
Ternary Ionic: Memorize me! NAME Chromate Cyanide Dichromate Hydroxide Nitrate Nitrite
FORMULA CHARGE CrO42-2 CN -1 2Cr 2O7 -2 OH -1 NO3-1 NO2-1
Ternary Ionic NAME
FORMULA NaNO3
Calcium phosphate Lithium carbonate NaClO3 Potassium permanganate Sodium bicarbonate
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Nomenclature & Formula Writing Binary
Binary Acids
acid
H + non-metal Hydro + -ic + acid
NAME Hydrochloric acid
FORMULA HI
Hydrosulfuric acid HF Hydrophosphoric acid
Nomenclature & Formula Writing Ternary
acid
H + polyatomic anions Rules: If
anion ends with –at e or –i d e : -ic + acid If it ends with –i t e : -ous + acid
NAME
FORMULA H2SO4
Sulfurous acid Nitric acid HNO2 H2CO3 Boric acid
Chemical Reaction & Balancing of Equation
Ternary Acid NAME
Ternary Acid
FORMULA H3PO4 HIO3
Acetic acid H2C2O4 HBrO3
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Direct Union or combination or Synthesis Combination of two or more elements A
+ B AB Hydrogen + Oxygen Sodium metal + Chlorine Magnesium ribbon burning
Decomposition Opposite
of synthesis
reaction AB B
+A Electrolysis of water
Single Displacement
Double displacement
A
Formation
+ BC
AC + B
Depends on activity series Mg + H2O
of two entirely different compounds Anions and cations switch together
Lead (II) Nitrate + Potassium iodide
Special
kind: Neutralization reaction
Strong acid + strong base HCl + NaOH
Combustion
Balancing of Equation
Reaction
By
with oxygen to form water and carbon dioxide C10H8 + 12O2 10CO2 + 4H2O
Inspection Algebraic Method By Redox-Reaction
NOTE:
In performing chemical reactions, it is required to balance the equations, if applicable.
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Figuring Out Oxidation Numbers
Rules in assigning ON
Oxidation
In
number
“charge” on an atom in a compound Rule: Assign a number (charge) to every atom
elemental form, ON = zero Hydrogen is always +1 (except in hydrides, where it is -1) Oxygen is always -2 (except in peroxides where it’s -1) Other atoms get the charge they prefer, as long as the SUM of all atom’s ON is the charge on the particle
Determine the charge of each element
Balancing of Equation: Redox Reaction
S8
AlH3
Acidic
H2O
KMnO4
H2O2
NaH2PO4
HCOOH
ClO4-
Solution Basic Solution
LiH
Thermodynamics
Thermodynamics
study
Thermodynamic System-
of energy, work, and heat and their inter-relation to one another
part of the universe isolated from the rest by a boundary
“Surrounding”
= Everything
outside
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Types of System
Important Terms
TYPE OF SYSTEM
ALLOWS EXCHANGE OF
Open (Nonconservative)
Matter & Energy
Closed (Conservative)
Energy ONLY
Isolated (Adiabatic)
No matter, No energy
TERM Heat Work
SYMBOL DESCRIPTION Q Energy transfer due to temperature difference w A form of energy transfer between and its surroundings in the form of compression or expansion of the gas
Important Terms
Important Terms
TERM SYMBOL DESCRIPTION Enthalpy H Represents heat; energy of a reaction Entropy S Determines the degree of randomness or disorderliness.
TERM Free energy
SYMBOL G
DESCRIPTION Represents the combined contribution of the enthalpy and entropy values for a chemical reaction.
Heat capacity
c
the amount of heat required to raise the temperature of an object or substance by one degree
A random, or disordered, system is characterized by high entropy; a well-organized system has low entropy. Gases > liquid > solid : entropy
Laws of Thermodynamics
Laws of Thermodynamics
1st Law
2nd Law
of Thermodynamics
Heat and work are forms of energy transfer. Energy is invariably conserved, however the internal energy of a closed system may change as heat is transferred into or out of the system or work is done on or by the system
of Thermodynamics
An
isolated system, if not already in its state of thermodynamic equilibrium, spontaneously evolves towards it. Thermodynamic equilibrium has the greatest entropy among the states accessible to the system.
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Laws of Thermodynamics
What you need to remember?
3rd Law
First
of Thermodynamics
The entropy of a system approaches a constant value as the temperature approaches zero The entropy of a system at absolute zero is typically zero, and in all cases is determined only by the number of different ground states it has. Specifically, the entropy of a pure crystalline substance at absolute zero temperature is zero
Law of Thermodynamics
“conservation of energy” Energy of the universe is constant
What you need to remember?
What you need to remember?
Second
Third
Law of Thermodynamics
Entropy Gibb’s Free Energy (expendable
Law of Thermodynamics
“entropy of a pure crystalline is equal to zero”
amount of energy)
ΔG(-)
= SPONTANEOUS ΔG(+) = NON-SPONTANEOUS ΔG(0) = Equilibrium
Chemical Kinetics
Question
the
An
study of the rate (or speed) of chemical reactions Exothermic reaction
releases energy to the surroundings surroundings become warmer
Endothermic
reaction
absorbs energy from the surroundings surroundings become colder
ice cube is dropped into a glass of water at room temperature. The ice cube melts. Is the melting of the ice exothermic or endothermic?
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Factors Affecting Reaction Rate
Chemical Equilibrium
structure
LE
of the reacting species molecular shape and orientation concentration of reactants temperature of reactants
The rate of a reaction increases as the temperature increases physical state of reactants
presence
CHATELIER’S PRINCIPLE
“…if a stress is placed on an equilibrium system, the system will respond by altering the equilibrium in such a way as to minimize the stress”
of a catalyst
A
catalyst is a substance that increases the reaction rate.
Factors Causing Equilibrium Shift
NUCLEAR CHEMISTRY
Pressure
Temperature/Heat Concentration Catalyst???
equilibrium
Types of Radiation
no shift of
decomposition process of unstable nuclei to more stable ones Radiation: energy and particles released during the decomposition process Radioactivity:
Units of Reactivity Non-SI
SI
Curie (Ci) : 1Ci = 3.7 x 10 10 decays/sec Bequerel (Bq) : 1Bq = 1 decay/sec
Unit
of R A D I A TI O N
Unit
of AMO UNT to radiation
: DAMA GE
R.E.M. OF EXPOSURE
rad or gray
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