Calculate the enthalpy of formation of methane given that the enthalpies of combustion of methane, graphite and hydrogen are 890.2 KJ, 393.4 KJ and 285.7 KJ `mol^(-1)` respectively

Explanation

To calculate the enthalpy of formation of methane (CH₄) using the given enthalpies of combustion, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given enthalpy values:**
- Enthalpy of combustion of methane (CH₄): ΔH_comb(CH₄) = -890.2 kJ/mol
- Enthalpy of combustion of graphite (C): ΔH_comb(C) = -393.4 kJ/mol
- Enthalpy of combustion of hydrogen (H₂): ΔH_comb(H₂) = -285.7 kJ/mol
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