Question

Complete combustion of 1.0 metric ton of coal (assuming pure carbon) to gaseous carbon dioxide releases 3.3 x 1010 j of heat. convert this energy to kilocalories

Answer 1

Keeping in mind that the conversion between calories and Joules is

`1 cal = 4.186 J`
we can write the conversion factor using the kilocalories:

`1 kcal = 4186 J`

The energy released in our problem is

`E=3.3 \cdot 10^(10) J`
so we can set a simple proportion to find its equivalent in kcal:

`1 kcal: 4186 J = x: 3.3 \cdot 10^(10) J`
from which we find:

`x= (3.3 \cdot 10^(10) J \cdot 1 kcal)/(4186 J) =7.88 \cdot 10^6 kcal`