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Question
ΔU⊖of combustion of methane is – X kJ mol–1. The value of ΔH⊖ is ______.
Options
= ΔU⊖
> ΔU⊖
< ΔU⊖
= 0
Solution
ΔU⊖of combustion of methane is – X kJ mol–1. The value of ΔH⊖ is < ΔU⊖.
Explanation:
Since ΔH⊖ = ΔU⊖ + ΔngRT and ΔU⊖ = - X kJ mol-1,
ΔH⊖ = (- X) + ΔngRT.
⇒ ΔH⊖ < ΔU⊖
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