Question

(Thermodynamics)

How much energy needs to be added to react of 20.0mol Cl_2 with excess CH_4? ∆H = 45.6 kJ

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Answer 1

456 kJ

Step-by-step explanation:

CH₄ + 2Cl₂ ⟶ CCl₄ + 2H₂ ; ΔH = 45.6 kJ

Treat the heat as if it were a product in the equation. Then use the molar ratio (45.6 kJ/2 mol Cl₂) in the usual way.

Amount of energy = 20 mol Cl₂ × (45.6 kJ/2 mol Cl₂) = 456 kJ

You must add 456 kJ to react 20 mol of chlorine with excess methane.