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Number of moles of methane required to produce 22 g CO2(g) after combustion is x 10-2 moles. The value of x is .
50
CH4(g) + 2O2(g) CO2(g) + 2H2O(l)
Moles of CO2 = 2244 = 0.5 mol
∵ 1 mol CH4 gives 1 mol CO2 ⇒ CH4 needed = 0.5 mol = 50 10-2 mol
Answer: 50
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