Question

For the reaction CO(g) + (1)/(2)O₂(g) → CO₂(g), which one of the statements is correct at constant T and P?

• A. \(\Delta H = \Delta E\)
• B. \(\Delta H < \Delta E\)
• C. \(\Delta H > \Delta E\)
• D. Δ H is independent of physical state of the reactants

Hint:

If gaseous moles decrease, then Δ H < Δ E.

Answer 1

The Correct Option is B

Step 1: Relation: Δ H = Δ E + Δ ng RT
Step 2: Change in moles of gas: Δ ng = 1 - (1 + \frac12) = -\frac12
Step 3: Since Δ ng < 0, Δ H < Δ E