Question

Chemical reactions in which large molecules are built from small molecules are classified as ______ reactions. In contrast, ______ reactions involve breaking large molecules down into smaller ones.

Answer 1

Exothermic and Endothermic Reaction

Explanation:

• Chemical reactions in which large molecules are built from small molecules are classified as exothermic reactions. During these reactions, a huge amount of energy is released.
• When bonds are formed to attain its stability there is the loss of energy as heat energy.  
• In contrast, Endothermic reactions involve breaking large molecules down into smaller ones. During this reaction, a large amount of energy is involved.
• When bonds break to attain its stability there is gain of energy.