Q. 3.30 - An Introduction to General, Organic, and Biological Chemistry

Question

Calculate the kilocalories for each of the following:

$\left(a\right)$ one cup of popcorn that produces$131kJ$ when burned in a calorimeter

$\left(b\right)$ a sample of butter that produces $23.4kJ$when burned in a calorimeter

Step-by-Step Solution

Answer

Part $\left(a\right)$

$\left(a\right)$ The converting energy into kilocalories as$131kJ=31.31kcal.$

Part $\left(b\right)$

$\left(b\right)$The converting energy into kilocalories as$23.4 KJ=5.6 kcal.$

Step: 1 Given information: (Part a)

One cup of popcorn is burned in a calorimeter given are: $131KJ$

To find one cup of popcorn burned in a calorimeter is converting into kilocalories. 

Step: 2 Converting intoKilocalories: (Part a)

Converting $131KJ$ into $kcal$

The factor as $1\mathrm{kcal}=4.184\mathrm{kJ}$

$131\mathrm{kJ}=131\mathrm{kJ}\times \frac{1\mathrm{kJ}}{4.184\mathrm{kcal}}$

As a result,

$131kJ=31.31kcal.$

Step: 3 Given information: (Part b)

Sample of butter is burned in a calorimeter given are: $23.4KJ$

To find sample of butter burned in a calorimeter is converting into kilocalories. 

Step: 4 Converting into Kilocalories: (Part b)

Converting$23.4 KJ$ into $kcal$

The factor as $1\mathrm{kcal}=4.184\mathrm{kJ}$

$23.4\mathrm{kJ}=23.4\mathrm{kJ}\times \frac{1\mathrm{kJ}}{4.184\mathrm{kcal}}$

As a result,

$23.4 KJ=5.6 kcal.$