Calculate the mass of coal that produces the same amount of energy as the combustion of 3.90 kg hydrogen gas. $$\begin{array} { l l }
\underline { \text { Fuel } } & \underline {\text { Energy released } ( \mathrm { kJ } / \mathrm { g } ) }\
\text { Coal } & 29 \
\text { Hydrogen } & 120
\end{array}$$

Question

Calculate the mass of coal that produces the same amount of energy as the combustion of 3.90 kg hydrogen gas. $$\begin{array} { l l } 
\underline { \text { Fuel } } & \underline {\text { Energy released } ( \mathrm { kJ } / \mathrm { g } ) }\
\text { Coal } & 29 \
\text { Hydrogen } & 120
\end{array}$$

Quizplus · Accepted Answer

The energy released by 3.90 kg (3900 g) of hydrogen is $3900 \, \text{g} \times 120 \, \text{kJ/g} = 468,000 \, \text{kJ}$. To find the mass of coal that releases the same energy, use $468,000 \, \text{kJ} \div 29 \, \text{kJ/g} = 16,137.93 \, \text{g}$, which is approximately $1.6 \times 10^4 \, \text{g}$.

Calculate the Mass of Coal That Produces the Same Amount