The heat of combustion of `CH_(4)(g), C_(2)H_(6)(g)` and `H_(2)(g)` are `-890.3, -1559,7` and `-285.9 kJ mol^(-1)`, respectively. Which of these fuels is most efficient?

Explanation

To determine which fuel is the most efficient based on the given heats of combustion, we will calculate the efficiency of each fuel using the formula:

\[ \text{Efficiency} = \frac{\text{Heat of combustion}}{\text{Molar mass}} \]

1. **Calculate the Molar Masses:**
- For Methane (CH₄):
- Carbon (C) = 12 g/mol
- Hydrogen (H) = 1 g/mol
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