What mass of methane (in g) must be burned in order to liberate 12567 kJ of heat?

Mass of methane required in gram = 226.35 gram (Approx.)

Explanation:

Given:

Heat energy used = 12,567 kJ

Missing data;

Δcombustion = 891  kJ/mol

Find:

Mass of methane required in gram

Computation:

Number of mol methane burned = Heat energy used / Δcombustion

Number of mol methane burned = 12,571 / 891

Number of mol methane burned = 14.1088 mol

1 mol of methane in gram = 16.043 grams

So,

Mass of methane required in gram = Number of mol methane burned x 1 mol of methane in gram

Mass of methane required in gram = 14.1088 x 16.043

Mass of methane required in gram = 226.3474

Mass of methane required in gram = 226.35 gram (Approx.)

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