Chemistry AP Review Flashcards (Video Notes)

Vocabulary-style flashcards covering key chemistry concepts from the notes (AP standards).

Molarity (M)

Concentration defined as moles of solute per liter of solution (mol/L).

Dilution

Process of lowering concentration by adding solvent; moles of solute stay the same.

Solute

Substance dissolved in a solvent.

Solvent

Substance in which another is dissolved; typically water in labs.

Concentrated Solution

A solution with high molarity; often used before dilution.

Theoretical Yield

Maximum amount of product that can be formed from given reactants based on limiting reactant.

Percent Yield

Actual yield divided by theoretical yield, expressed as a percentage.

Limiting Reactant

Reactant that limits the amount of product formed; determines theoretical yield.

Stoichiometry

Numerical relationships between reactants and products in a balanced chemical equation.

Balanced Chemical Equation

Equation with equal numbers of each type of atom on both sides; coefficients balance atoms, not subscripts.

Skeletal Equation

Unbalanced equation showing formulas for reactants and products.

Empirical Formula

Simplest whole-number ratio of atoms in a compound.

Molecular Formula

Actual number of each type of atom in a molecule; may be a multiple of the empirical formula.

Percent Composition

Percent by mass of each element in a compound; often based on a 100 g sample.

Empirical vs Molecular Formula

Empirical is the simplest ratio; molecular shows total atoms; they can be the same or a multiple.

Binary Molecular Compound

A compound composed of two nonmetals.

Monatomic Ion

Ion consisting of a single atom (cation or anion).

Polyatomic Ion

Ion made up of multiple atoms, usually containing oxygen.

Cation

Positively charged ion (loses electrons).

Anion

Negatively charged ion (gains electrons).

Hydrocarbons

Organic compounds containing only carbon and hydrogen.

Alkanes

Hydrocarbons containing only single bonds.

Alkenes

Hydrocarbons with at least one C=C double bond.

Alkynes

Hydrocarbons with at least one C≡C triple bond.

Alcohol

Functional group -OH; class of organic compounds.

Carboxylic Acid

Functional group -COOH; organic acids.

Binary Acids

Acids composed of hydrogen and a non-metal (e.g., HCl).

Oxyacids

Acids containing hydrogen and an oxyanion (e.g., H2SO3).

Atomic Number (Z)

Number of protons in an atom; defines the element.

Mass Number (A)

Sum of the protons and neutrons in the nucleus.

Isotopes

Atoms of the same element with different numbers of neutrons; natural abundances vary.

Avogadro's Number

6.022 x 10^23 representative units per mole.

Molar Mass

Mass of one mole of a substance (g/mol); numerically equal to amu for elements.

Molar Mass vs Molarity

Molar Mass is mass per mole (g/mol); Molarity is concentration (mol/L).

Conservation of Mass

Matter is neither created nor destroyed in a chemical reaction.

Definite Proportions (Constant Composition)

A given compound has the same element mass ratio in all samples.

Law of Multiple Proportions

When two elements form different compounds, the masses of one element that combine with a fixed mass of the other are in small whole-number ratios.

Dalton's Atomic Theory

Atoms form compounds; atoms of the same element are identical; atoms combine in simple ratios; atoms rearrange, not created/destroyed.

Significant Figures

Rules for counting meaningful digits in measurements: nonzero digits, captive zeros, leading zeros not significant, trailing zeros with a decimal are significant.

Decimal Places (Addition/Subtraction)

Final answer should have as many decimal places as the value with the fewest decimals.

Significant Figures (Multiplication/Division)

Final answer should have as many significant figures as the value with the fewest sig figs.

Empirical Formula from Percent

Use percent composition (basis 100 g) to determine mole ratio of elements, then reduce to smallest whole numbers.

Homogeneous Mixture

Uniform composition throughout; same properties in any sampled part.

Heterogeneous Mixture

Not uniform; different regions have different compositions.

Element

Pure substance consisting of one type of atom; may exist as atoms or diatomic molecules.

Compound

Pure substance composed of two or more different elements in fixed ratio.

Diatomic Element

Element that naturally exists as two atoms in its elemental form (e.g., O2).

Mixture Separation by Physical Means

Mixtures can be separated by physical methods (filtration, distillation, etc.).