Question

The standard enthalpies of formation of $\mathrm{CH_4(g)}$, $\mathrm{CO_2(g)}$ and $\mathrm{H_2O(l)}$ are $-78$, $-395$ and $-288\ \mathrm{kJ\ mol^{-1}}$ respectively. Calculate $\Delta H$ for: \[ \mathrm{2CH_4(g) + 4O_2(g) \rightarrow 2CO_2(g) + 4H_2O(l)} \] }

• A. $+890.3$
• B. $-890.3$
• C. $-1780.6$
• D. $+1780.6$

Hint:

Always remember: \[ \Delta H = \text{Products} - \text{Reactants} \] A negative value of $\Delta H$ indicates that the reaction is exothermic.

Answer 1

The Correct Option is C