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Question
Write the mathematical relation between ΔH and ΔU during the formation of one mole of CO2 under standard conditions.
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Solution
Formation of one mole of CO2 under standard conditions:
\[\ce{C_{(s)} + O_{2(g)} -> CO_{2(g)}}\]
Δng = (moles of product gases) − (moles of reactant gases)
Δng = 1 – 1 = 0
Now, ΔH = ΔU + ∆ngRT
ΔH = ΔU + 0 × RT
∴ ΔH = ΔU
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