Question

The combustion of 44.45 grams of a hydrocarbon gas mixture releases 2,649 kJ of heat. How much energy, in kWh, will the combustion of exactly one pound of this hydrocarbon gas produce? There are 453.592 g in 1 lb. Please express your answer to the appropriate number of significant figures. Your Answer:

Answer 1

Step-by-step explanation:

It is given that 44.45 g of hydrocarbon gas produces 2649 kJ or
`2649 * 10^(3) J` of heat.

Also here, 1 lb = 453.592 g.

Therefore, amount of energy released by 453.592 g of hydrocarbon gas will be calculated as follows.

`(2649 * 10^(3) J * 453.592 g)/(44.45 g)`

=
`27.03 * 10^(6) J`

It is known that 1 J =
`2.778 * 10^(-7) Kwh`.

Hence,
`27.03 * 10^(6) J` =
`27.03 * 10^(6) J * 2.778 * 10^(-7) Kwh/J`

= 7.508 Kwh

Thus, we can conclude that the combustion of exactly one pound of this hydrocarbon gas produce 7.508 Kwh energy.