Chapter 9, Problem 9.43EP

(a)

Interpretation Introduction

Interpretation

For which chemical reaction, the average energy of the products is lower than the average energy of the reactants has to explained.

Concept Introduction:

Exothermic Reactions:

The chemical reaction in which heat energy is released known as exothermic reaction.  The chemical bond will determine whether the reaction is exothermic or endothermic.  If the energy released by bond formation is greater than the energy required to break the bond, then the reaction is said to exothermic.

Examples for exothermic reaction:

• Making ice cubes.
• Formation of snow in clouds.
• Condensation of rain from water vapour.
• Rusting iron.
• Burning sugar.

(b)

Interpretation Introduction

Interpretation

For which chemical reaction, the energy released or absorbed has to explained.

Concept Introduction:

Exothermic Reactions:

The chemical reaction in which heat energy is released known as exothermic reaction.  The chemical bond will determine whether the reaction is exothermic or endothermic.  If the energy released by bond formation is greater than the energy required to break the bond, then the reaction is said to exothermic.

Examples for exothermic reaction:

• Making ice cubes.
• Formation of snow in clouds.
• Condensation of rain from water vapour.
• Rusting iron.
• Burning sugar.