Chapter U5, Problem 6RE

Interpretation Introduction

Interpretation: The calories of thermal energy that must be transferred to heat up a100 g aluminium pot from 20 ^oC to 80 ^oC needs to be determined.

Concept Introduction:

The amount of energy transferred for the given mass of substance can be calculated as follows:

  $q=mc\Delta T$

Here, m is mass, c is specific heat capacity and $\Delta T$ is change in temperature.

Answer to Problem 6RE

1260 cal.

Explanation of Solution

The specific heat capacity of aluminium is 0.21 cal/g ^oC. The mass of aluminium pot is 100 g. Also, the initial and final temperature is 20 ^oC and 80 ^oC respectively.

The calories of energy required to raise the temperature of aluminium can be calculated as follows:

  $q=mc\Delta T$

Putting the values,

  $q=\left(100\text{ g}\right)\left(\text{0}{\text{.21 cal/g }}^{\text{o}}\text{C}\right)\left(\text{80}-20{}^{\text{o}}\text{C}\right)=1260\text{ cal}$

Thus, the calories of thermal energy that must be transferred to heat up a 100 g aluminium pot is 1260 cal.