Q.3.85 - An Introduction to General, Organic, and Biological Chemistry

Question

A 0.50-g sample of vegetable oil is placed in a calorimeter. When the sample is burned, 18.9 KJ is given off. What is the energy value (kcal/g) for the oil? 

Step-by-Step Solution

Answer

energy value (kcal/g) for the oil is$9kcal/g$

Step 1: Given Information

Mass = $0.5g$

the energy released while burning = $18.9kJ$

Step 2: Explanation

we know,

$1\mathrm{kJ}=0.239\mathrm{kcal}$

$\Rightarrow 18.9\mathrm{kJ}=0.239\times 18.9=4.52\mathrm{kcal}$

$4.52kcal$ is released from $0.5g$ of oil

Hence the energy released per gram is 

$\frac{4.52\mathrm{kcal}}{0.5\mathrm{g}}=9.0\mathrm{kcal}/\mathrm{g}$