For CH₄(g) + 2 O₂(g) → CO₂(g) + 2 H₂O(l), ΔS° is

Likely negative (fewer gas moles after H₂O condenses) 3 mol gas → 1 mol gas (with liquid water); decrease in gas moles makes ΔS° negative.

Likely negative (fewer gas moles after H₂O condenses)

Absolute Entropy and Entropy Change

AP Chemistry· difficulty 3/5

For CH₄(g) + 2 O₂(g) \to CO₂(g) + 2 H₂O(l), ΔS° is

Explanation

3 mol gas \to 1 mol gas (with liquid water); decrease in gas moles makes ΔS° negative.

Want 10 more like this — adaptive to your weak spots?