Question

Which of these is true of a chemical reaction? Energy is always released. Energy is not transferred. Energy is always absorbed. Energy is either released or absorbed.

Answer 1

energy is either realesed or absorbed

Answer 2

Among the given statements, The following is true about chemical reaction:

"Energy is either absorbed or released"

Reason :

When ever chemical reaction occurs energy changes are involved :

1. Exothermic reaction

2. Endothermic reaction

Exothermic reaction :

When ever heat is released out of chemical reaction.

eg: CaO   +  H2O -----------> Ca(OH)2 +heat

Endothermic reaction :

When heat absorbed during chemical reaction.

example photosynthesis occurs by absorbing light energy