AP Chem Unit 1

Observe

Macroscopic

Imagine

Particulate

Represent

Symbolic

How we study nature

Scientific Method

Observation

Collecting data

Qualitative

Descriptive characteristics

Quantitative

Number and Unit

Hypothesis

making predictions

Experiments

testing hypothesis

Theory

accepted explanation of WHY nature behaves a certain way

Law

FACTS summarizing HOW nature behaves

2 Types of Pure substances

elements and compounds

Elements are made up of

Atoms (elemental symbol)

Compounds are made up of

Molecules (chemical formula)

How are Elements separated

Only able to be separated by Nuclear Means

How are Compounds separated

Only able to be separated by Chemical Means

Types of Elements

Monoatomic and Diatomic

Types of Compounds

Covalent (share electrons) and Ionic (transfer electrons)

Diatomic Elements

H2, N2, O2, F2, Cl2, Br2, I2

Monoatomic Elements

composed of single atoms not bonded to each other

Covalent Compounds are made up of

All Nonmetals

Ionic Compounds are made up of

A Metal and a Nonmetal

Covalent Compounds make

Molecules

Ionic Compounds make

Crystal Lattices

Two Types of Mixtures

Homogenous and Heterogenous

Homogenous Mixture

A uniform mixture

Heterogenous Mixture

A nonuniform mixture

Properties of Matter

physical and chemical

Physical Properties

Observed without altering the chemical makeup

Chemical Properties

Once observed chemical makeup changes

Intensive

Independent of the amount of a substance

Extensive

Depends on the amount of substance

Types of Intensive Properties

melting point, boiling point, density, ability to conduct electricity, ability to transfer energy as heat

Types of Extensive Properties

volume, mass, amount of energy in a substance

Types of Chemical Properties

corrosiveness, flammability, acidity, toxicity

Centrifuge and Decanting

solid & liquid (insoluable)

Centrifuge and Decanting is

Qualitative

Distillation

Volatile liquid vaporizes first (homogenous)

Filtration

Solid & liquid (insoluble)

Gravity Filtration is

Quantitative

Vacuum Filtration is

Qualitative

Two Types of Filtration

Gravity Filtration and Vacuum Filtration

Evaporation Crystallization

Soluble solid in liquid

Chromatography

Different Colored Substances

Accuracy

how close a measurement is to the true value

Precision

The degree to which repeated measurements show the same result.

% error

theoretical-experimental/theoretical x 100

% difference

trial 1-trial2/average x 100

Law of Definite Proportions

Atoms combine in whole # ratios

Law of Multiple Proportions

Atoms can combine in different ratios

% Composition

mass of part/mass of whole x 100

Empirical Formula

Lowest whole number of atoms ratio

Steps for Empirical Formula

1. If the percent is given, assume a 100 g sample so that percent is equal in grams
2. Change Grams to moles
3. Get the smallest whole number ration— divide each result from step two by the smallest result
4. If necessary (like if it is a .5 or something), multiply by whole number
5. Write the empirical formula

Molecular Formula

actual ratio of atoms

Franklin

Opposites Attract

Lavoisier

Law of multiple and definite proportions

Milkan

Mass of the electron

Dalton

atomic theory

Thompson

Plum Pudding and Catharay Tube

Rutherford

Gold Foil and Nucleus

Bohr

Energy Levels

Schrodinger

Electron Cloud

Counting Subatomic Particles

Mass # over Atomic #

Mass #

# of protons + # of neutrons

Atomic #

# of protons

For any given element, the size of an isotope with more neutrons is larger than one with fewer neutrons

FALSE - an e- determines the size

For a given element, the size of an atom is the same for all of the element's isotopes

TRUE - Masses would be different not size

Atomic Mass

Average mass of all the isotopes of that element

Atomic Mass Steps

1. Convert % abundance to decimal
2. Multiply decimal by mass of each atom
3. Add them together

Oxidation Numbers Rule 1

An element in its natural form (not combined with another element) has an oxidation number of 0

Oxidation Numbers Rule 2

Monoatomic metal ions in Groups 1 & 2 have oxidation # equal to their charge

Oxidation Numbers Rule 3

Oxygen has an oxidation # of -2; Except when it's in a peroxide (Metal O2) where each oxygen is -1

Oxidation Numbers Rule 4

Hydrogen has an oxidation # of +1; Except in metal hydrides (MxHy), then its -1

Oxidation Numbers Rule 5

Halogens are -1; Except when combined w/ O or F

Oxidation Numbers Rule 6

Sum of all oxidation #'s must add to zero or the charge of the ion

Prefix 1

Mono

Prefix 2

Di

Prefix 3

Tri

Prefix 4

Tetra

Prefix 5

Penta

Prefix 6

Hexa

Prefix 7

Hepta

Prefix 8

Octa

Prefix 9

Nona

Prefix 10

Deca

Phosphate

PO4 3-

Sulfate

SO4 2-

Chlorate

ClO3 1-

Carbonate

CO3 2-

Nitrate

NO3 1-

Hydroxide

OH 1-

Acetate

C2H3O2 1-

Polyatomic Anion Name

Per____ate
____ate
____ite
Hypo____ite
____ide

Acid Name

Per____ic acid
____ic acid
____ous acid
Hypo____ous acid
Hydro____ic acid

5 Steps to Limiting Reactant Problems

1. Write BCE
2. Determine the moles of each reactant initial (goes in ICE)
3. Determine the number of moles that react (change) with the mole ratio.
4. Determine the limiting reactant by setting initial - change = 0 for both reactants. Whichever is the smallest x is the Limiting Reactant.
5. Use the limiting reactant to answer the question. Use the excess reactant to determine whats leftover.

Making a Solution from a Solid

1. Mass the amount of solid
2. Fill the size volumetric flask 1/3 to 1/2 full with distilled water
3. Transfer the Solid to a Volumetric Flask
4. Swirl until dissolved (add more water if necessary)
5. Fill the flask with distilled water until the bottom of the meniscus touches the etched mark
6. Cap & Invert or Pour into a Beaker and Parafilm

Making a Solution by Dilution (from Stock)

1. Determine the molarity needed, amount needed, and tock concentration (use to determine the pipet size)
2. Obtain Pipet and Volumetric Flask
3. Pipet stock into a volumetric flask, be sure to touch the tip of the side
4. Fill the rest of the flask with distilled water until the bottom of the meniscus touches the etched mark
5. Cap & Invert or Pour into a Beaker and Parafilm

Making a Solution by Dilution FORMULA

M1 (Thing in pipet or stock) V1 = M2 V2 (amount of diluted)

Strong Electrolytes

Dissociates completely when dissolved in water

Strong Electrolytes Examples

Strong Ionic Compounds (salts
Strong Bases
Strong Acids