Unit 6 Vocabulary Honors Chem

Mole

Amount of a substance that contains as many particles as there are atoms in exactly 12 g of carbon-12

Stoichiometry

The study of the mass-mole-number relationships of chemical formulas and reactions

Law of Conservation of Mass

A mass law stating that the total mass of substances does not change during a chemical reaction

Avogadro's number

6.022 × 1023 —is the number of particles in exactly one mole of a pure substance

Molar Mass

The mass in grams of 1 mole of a substance

Chemical Equation

A statement that uses chemical formulas to express the identities and quantities of the substance involved in a chemical or physical change

Chemical Formula

Symbols that show the elements in a compound and the ratio of atoms

Coefficient

A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction

Reactant

A starting substance in a chemical reaction

Product

A substance formed in a chemical reaction

Percent Composition

The percentage by mass of each element in a compound

Empirical Formula

A chemical formula that shows the lowest relative numbers of atoms of elements in a compound

Molecular Formula

A formula that shows the actual number of atoms of each element in a molecule

Limiting Reactant

The reactant that is consumed when a reaction occurs and therefore the one that determines the maximum amount of product that can form

Excess Reactant

The reactant that is not completely used up in a chemical reaction

Theoretical Yield

The amount of product predicted by the stoichiometrically equivalent molar ratio in the balanced equation

Actual Yield

The amount of product actually obtained in a chemical reaction

Percent Yield

The actual yield of a reaction expressed as a percentage of the theoretical yield

Concentration

A measure of the quantity of solute dissolved in a given quantity of solution

Dilution

The process of adding solvent to lower the concentration of solute in a solution

Molarity

A concentration term expressed as the moles of solute dissolved in 1 L solution

Solute

The substance that dissolves in the solvent

Solvent

The substance in which the solute(s) dissolve