Chapter 9, Problem 86CP

(a)

Interpretation Introduction

Interpretation:

Whether the given reaction is endothermic or exothermic needs to be determined.

Concept Introduction :

For a reaction, if heat is required or added then reaction is endothermic and if heat is released then reaction is exothermic.

(b)

Interpretation Introduction

Interpretation:

The amount of heat in kcal produced from 5.0 g of ethanol needs to be determined.

Concept Introduction :

The relation between number of moles and mass is as follows:

  $n=\frac{m}{M}$

Here, m is mass and M is molar mass.

(c)

Interpretation Introduction

Interpretation:

The mass of ethanol if 1250 kJ of heat is produced needs to be determined.

Concept Introduction :

The relation between number of moles and mass is as follows:

  $n=\frac{m}{M}$

Here, m is mass and M is molar mass.