Predict the Sign of ΔS

Question

Which of the following transformations represent an increase in the entropy of the system.

Choose all that apply

1. 46 g Hg (liquid, 615K)46 g Hg (liquid, 249K)
2. 2 mol He (1.32 atm, 205K)2 mol He (1.32 atm, 411K)
3. 1 mol CH₄ (6.35 L, 243K)1 mol CH₄ (12.7 L, 243K)
4. 46 g Hg (gas, 630K)46 g Hg (liquid, 630K)
5. 18 g Pb (solid, 601.0K)18 g Pb (liquid, 601.0K)

Answer 1

The following represent in increase in entropy (+∆S)

 2 mol He (1.32 atm, 205K) ==> 2 mol He (1.32 atm, 411K)

 1 mol CH4 (6.35 L, 243K) ==> 1 mol CH4 (12.7 L, 243K)

 18 g Pb (solid, 601.0K) ==> 18 g Pb (liquid, 601.0K)

The others would be a decrease (-∆S) in entropy