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7.1 Stoichiometry—What is it?- Quantities in a chemical reactions
7.2 Mole: Counting Atoms by the Gram
A. Pair =2; dozen = 12; 1 mole = 6.02 x 1023
B. 1 mole of Au atoms = 6.02 x 1023 Au atoms
C. The periodic table gives the mass of 1 mole of that atom in grams
1 mole of S atoms = 32.06 g S ; 1 mole of C atoms = 12.01 g C
D. Unit conversions between grams and moles of atoms
Moles = grams/Molar mass
Extend idea to Molecules by the Gram
A. Mass of 1 mole H2O = mass of 2 moles of H + 1 mole O
B. Calculations performed in a similar fashion
Chemical Formulas as Conversion Factors
A. Molecular formula gives ratios of atoms in molecule
B. Converting moles of atoms to moles of molecules
C. Converting grams of atoms to grams of molecules
7.3 Learn the % composition- EASY!!!
Mass Percent Composition of Compounds
A. Percentage of molecule's total mass that is due to atom X
B. Convert between mass of element and mass of compound
C. Mass Percent Composition from a Chemical Formula
7.5 and 7.6 Calculating Empirical Formulas for Compounds
A. Empirical formula is the smallest whole number ratio of atoms
B. Mostly different from molecular formula
C. Many different compounds may have the same empirical formula
Calculating Molecular Formulas for Compounds
A. Empirical formula molar mass
B. Compare molar mass to empirical formula mass
C. Ration= (Molar mass/emp. Mass) = (molecular formula/Emp. Formula)
D. Ratio n is the nearest whole number
4 steps in Empirical formula problem
1) % to grams
2) Grams/Molar mass = Moles
3) Divide all moles by Smallest moles
4) Use appropriate rounding to get Empirical formulas
Chapter 9 Chemical Reactions
Sections (9.2, 9.3 9.4,and 9.5) omit Rest of the sections
• Moles  moles of reactants and products
– Start from Balanced chemical Equation
– Moles is like cups in a recipe
– In moles to moles problem – Moles from Balanced chemical equation
– NO NEED TO CALCULATE molar mass, Avogadro number etc.
• Grams Grams of reactants and products
– Start from Balanced chemical Equation
– Calculate the molar masses for things in question
– Multiply by the coefficients with molar masses for stoichiometric
equivalence
• Moles  Grams of reactants and products
– Moles = weight in grams/molar mass
Chapter 12 Gases (Omit all Math Problems)
Describing the Ideal Gas
Kinetic Molecular Theory: A Model for Gases
A. A gas is a collection of particles in constant straight line motion
B. Particles neither attract nor repel one another
C. Between species is mostly empty space
D. Average kinetic energy proportional to absolute (Kelvin)
temperature
Pressure: The Result of Constant Molecular Collisions on the wall
A. Pressure = force/area
B. Units of pressure: Atmosphere (atm), Millimeter of mercury (mm Hg)
Torr; Pounds per square inch (psi); Pascal (Pa)
Boyle's Law: Pressure and Volume
A. P  1/V or P is inversly proportional to V
B. Temperature and number of moles must be constant
P1V1 = P2V2
Charles's Law: Volume and Temperature
A. V  T– Directly proportional
B. Pressure and number of moles of gas must be constant
Avogadro's Law: Volume and Moles
A. V  n
B. Pressure and temperature must be constant
Rule 1: P is proportional to 1/V
P α 1/V
Rule 2: P is proportional to T
Rule 3: P is proportional to n
Overall P α nT/V
PV = nRT
V1 V2

T1 T2
V1 V2

n1 n 2
 P1V1   P1V2 



n
T
n
T
 1 1  2 2
IDEAL GAS LAW, where P is pressure, V is Volume,
T is Temperature, n is # of moles, R is gas constant
Chapter 13 Intermolecular Forces water
Why Does Matter Exist in Different Phases?
Interactions between Molecules
•
Intermolecular forces
•
Thermal energy = energy of motion
A. Properties of solids
• Highest Intermolecular forces
• Definite shape and Volume
B. Properties of liquids
• Weaker Intermolecular forces compared to solids, stronger than gases
• Definite Volume NO shape
C. Properties of Gases
• Weakest Intermolecular forces
• No Definite Volume or shape, Lowest Density
Evaporation and Condensation
A. Evaporation and vaporization – liquid to gas
B. Condensation – gas to liquid
C. Boiling, Boiling Point
D. Energy change going from liquid to gas is to overcome stronger
intermolecular forces in liquids
Types of Intermolecular Forces: Dispersion, Dipole-Dipole, and
Hydrogen Bonding
A. Dispersion force, also known as London forces
1. Weakest intermolecular force due to Instantaneous dipole
2. Involved in every molecule/atom intermolecular interaction
3. Increases with molar mass
4. Only operative force for non-polar molecules
B. Dipole-dipole force- IN POLAR MOLECULES ONLY
1. Stronger force than dispersion forces
2. Strength a function of dipole moment and structure
C. Hydrogen bonding
1. Strongest intermolecular forces
2. Only involving F, O, or N bonded to a hydrogen atom
D. Ionic Bonding Both inter and Intra molecular force, stronger than rest of the
intermolecular forces mentioned above
STRONGER intermolecular forces are Higher is the Boiling and Melting points
Properties of water
Chapter 14 SOLUTIONS
14.1 What is Solution?: Homogeneous Mixtures
A. Any homogenous mixture is a solution
B. Solvent: major component
C. Solute: minor component, can be more than one
14.2 Energetics in Solution?: Dissociation in solution into Ions, Ion-Dipole forces
Solutions of Solids Dissolved in Water
A. Solubility and Saturation
1. Saturated: solvent holding as much solute as it can
2. Unsaturated: solvent can hold more solute
3. Supersaturated: solvent holding more than the maximum amount of solute
B. Solubility is temperature dependent
(Solid in liquid, solubility increases with temperature)
C. How to make saturated solutions
D.Miscibility- Like dissolves Like- Check Lab#8
Solutions of Gases in Water:
A. Solubility increases with pressure ; and DECRESES with temperature
B. Dilute vs. concentrated
Specifying Solution Concentration: Mass Percent
mass solute
x 100%
A. Mass percent =
mass solution
Remember that Mass of solution
= mass solvent + mass solute
B. B. Conversion factor between amount of solution and amount of a particular
solute
Specifying Solution Concentration: Molarity
A. Molarity (M) =
moles solute
liters solution
B. Volume of solution in L, not just solvent
C. Units always mol/L
Dilution McVc = MdVd
12.8 Solution Stoichiometry -TITRATIONS
A. Balanced chemical equations give molar ratios only
At end point moles of Acid = moles of Base
B. Convert volume to moles using molarity, then use balanced chemical
equation
Chapter 15 (10%)
Definition of Acids-
Definition of Bases-
Arrhenius- produce H+
Bronsted-Lowry: H+donor
Lewis concept: electron acceptor
Arrhenius- produce OHBronsted-Lowry: H+acceptor
Lewis concept: electron donor
Properties and reactions of Acids- Metal + Acid - ? (check lab book also)
Acid + Base - ? + ?
Weak and strong electrolytes (refer to lab): NEED IONS!!
; Strong acids: HCl, HBr, HI, HNO3, H2SO4, HClO4
strong base: Group IA hydroxide, group IIA hydroxide
Salts soluble in H2) is strong electrolyte
Soluble salts?? Salts containing Group IA cations, NH4+, , NO3Cl-, Br-, I- salts all soluble except with Ag+, Pb+2,,
Sulfates All soluble except with Ba+2, Ca++2, Sr+2, Pb+2
pH<7 : Acid; pH>7 bases, pH=7 neutral