Chemical Reactions and Energy

The burning of gasoline in an automobile engine is an example of a(n) _____.

• photosynthesis reaction

• endothermic reaction

• exothermic reaction

• reversible reaction

In a chemical change, energy can be _____.

• created, but not destroyed

• destroyed, but not created

• either created or destroyed

• neither created nor destroyed

In a(n) _____ reaction, the products are at a higher energy level than are the reactants.

• activation

• catalytic

• endothermic

• exothermic

The energy involved in endothermic and exothermic reactions is _____.

• chemical

• thermal

• light

• electrical

Why are fossil fuels a rich source of energy?

• fossil fuels require activation energy to burn

• fossil fuels are millions of years old

• heat is released when fossil fuels combine with oxygen

• carbon dioxide is released when fossil fuels combine with oxygen

If energy must be added to a chemical reaction for the reaction to take place, the reaction is ____.

• balanced

• endothermic

• exothermic

• reactant

A chemical reaction in which thermal energy is released is ____.

• endothermic

• exothermic

• flammable

• a formula

When most chemical reactions take place, some ____ in the reactants must be broken, a process that requires energy.

• compounds

• chemical bonds

• precipitates

• products

​Exothermic reactions do not require any activation energy.

• True

• False

​All chemical reactions occur at the same rates.

• True

• False