The quantity of heat from a chemical reaction comes from:
A)The breaking and formation of chemical bonds.
B)The presence of oxygen in the reaction.
C)The emission of radiation.
D)The composition of the fuel-air mix.

Question

Quizplus · Accepted Answer

The heat from a chemical reaction is primarily due to the energy changes associated with the breaking of old chemical bonds and the formation of new ones. Energy is absorbed to break bonds and released when new bonds are formed; the net heat released or absorbed in a reaction depends on these bond energy changes.

The Quantity of Heat from a Chemical Reaction Comes From