8th Grade Chapter 9 Chemical Reactions and Equations

The atoms in the products of a chemical equation

• were present in the reactants

• did not exist before the reaction

• were created using energy from the reaction

In a chemical reaction, energy is released

• only when bonds are broken

• only when bonds are formed

• when bonds break and when bonds form

A chemical reaction that has two products and two reactants could be a

• synthesis reaction

• decomposition reaction

• double-replacement reaction

Which procedure would cause a chemical reaction to speed up?

• lowering the temperature of the reactants

• increasing the surface area of the reactants

• reducing the concentration of the reactants

In a chemical reaction, the mass of the products is always

• equal to the mass of the reactants

• less than the mass of the reactants

• greater than the mass of the reactants

In a chemical reaction, what is activation energy required for?

• to form each of the bonds in the products

• to begin breaking the bonds of the reactants

• to provide enough energy for the entire reaction to occur

A starting substance in a chemical reaction

• reactant

• combustion

• product

• inhibitor

Occurs when a substance combines with oxygen and releases energy

• reactant

• combustion

• product

• inhibitor

A new substance produced in a chemical reaction

• reactant

• combustion

• product

• inhibitor

A substance that slows down or stops a chemical reaction

• reactant

• combustion

• product

• inhibitor