Stoichiometry of Chemical Reactions

Vocabulary flashcards covering core topics in general chemistry stoichiometry, including equations, reaction types, formula weights, mole concept, limiting reactants, and percent yields.

Chemical Equation

A concise representation of a chemical reaction, showing reactants on the left side and products on the right side.

Reactants

Substances that appear on the left side of a chemical equation and are consumed during a chemical reaction.

Products

Substances that appear on the right side of a chemical equation and are formed as a result of a chemical reaction.

Coefficient

A number inserted in front of a chemical formula to balance an equation, indicating the relative number of molecules or moles of that substance.

Subscript

A number written lower and to the right of an element symbol in a formula that indicates the number of atoms of that element in a molecule.

Combination Reaction

A reaction type in which two or more substances react to form a single product.

Decomposition Reaction

A reaction type in which one substance breaks down into two or more substances.

Combustion Reaction

A rapid reaction that produces a flame, most often involving hydrocarbons reacting with oxygen in the air.

Formula Weight (FW)

The sum of the atomic weights for all the atoms in a chemical formula, generally reported for ionic compounds.

Molecular Weight (MW)

The sum of the atomic weights of all the atoms in a molecule.

Percent Composition

The percentage of a compound's mass contributed by each element, calculated as $\% \text{Element} = \frac{(\text{number of atoms})(\text{atomic weight})}{\text{FW of the compound}} \times 100$.

Avogadro's Number

The value $6.02 \times 10^{23}$, which represents the number of particles contained in $1\,\text{mole}$ of any substance.

Molar Mass

The mass of $1\,\text{mol}$ of a substance, expressed in units of $\text{g/mol}$.

Limiting Reactant

The reactant present in the smallest stoichiometric amount that is completely consumed first and determines the maximum amount of product formed.

Theoretical Yield

The maximum amount of product that can be made in a chemical reaction, as calculated through stoichiometry.

Actual Yield

The amount of product that is actually produced and measured in an experiment.

Percent Yield

The ratio comparing actual product yield to theoretical yield, calculated as $\text{Percent yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100$.