Chapter 5, Problem 81E

Among the substances that react with oxygen and that have been considered as potential rocket fuels are diborane [ ${\text{B}}_2{\text{H}}_6$, produces ${\text{B}}_2{\text{O}}_3\left(s\right)$ and ${\text{H}}_2\text{O}\left(g\right)$ ], methane [ ${\text{CH}}_4$, produces ${\text{CO}}_2\left(g\right)$ and ${\text{H}}_2\text{O}\left(g\right)$ ], and hydrazine [ ${\text{N}}_2{\text{H}}_2$, produces ${\text{N}}_2\left(g\right)$ and ${\text{H}}_2\text{O}\left(g\right)$ ]. On the basis of the heat released by 1.00 g of each substance in its reaction with oxygen, which of these compounds offers the best possibility as a rocket fuel? The $\Delta H_{\text{f}}^{°}$ of ${\text{B}}_2{\text{H}}_6\left(g\right)$, ${\text{CH}}_4\left(g\right)$, and ${\text{N}}_2{\text{H}}_4\left(l\right)$ may be found in Appendix G.