# Problem: The methane molecule, CH4, has the geometry shown in following figure. Imagine a hypothetical process in which the methane molecule is "expanded," by simultaneously extending all four C–H bonds to infinity. We then have the process CH4(g) → C(g) + 4 H(g).Suppose that 3.45 g CH4(g) reacts with 1.22 g F2(g), forming CF4(g) and HF(g) as sole products. If the reaction occurs at constant pressure, what amount of heat is evolved?

###### FREE Expert Solution

Balanced reaction: CH4(g) + 4 F2(g) → CF4(g) + 4 HF(g)

ΔH˚rxn = –1952.2 kJ/mol

Find the limiting reactant:

HF from CH4:

molar mass CH4 = 16.042 g/mol

moles HF = 0.860 mol HF

HF from F2:

82% (479 ratings) ###### Problem Details
The methane molecule, CH4, has the geometry shown in following figure. Imagine a hypothetical process in which the methane molecule is "expanded," by simultaneously extending all four C–H bonds to infinity. We then have the process CH4(g) → C(g) + 4 H(g). Suppose that 3.45 g CH4(g) reacts with 1.22 g F2(g), forming CF4(g) and HF(g) as sole products. If the reaction occurs at constant pressure, what amount of heat is evolved?

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