Question

12) Predict the sign of AS of the system for both of the following. I. 2 C(graphite) + O2(8) - 2 CO(8) II. C6H14(8) - C6H14(1) A) AS should be positive for I and positive for II. B) AS should be negative for I and positive for II. C) AS should be positive for I and negative for II. D) AS should be negative for I and negative for II. 13) If Q increases, A) AG increases and the reaction becomes less spontaneous. B) AG decreases and the reaction becomes less spontaneous. C) AG increases and the reaction becomes more spontaneous. D) AG decreases and the reaction becomes more spontaneous.

Answer 1

12)

entropy of gas > entropy of aqueous > entropy of liquid > entropy of solid

I)

There are gases only on product side.

So, there is more entropy on product side than on reactant side.

So, there is increase in entropy

Delta S will be positive

II)

There are gases only on reactant side.

So, there is more entropy on reactant side than on product side.

So, there is decrease in entropy

Delta S will be negative

Answer: C

13)

ΔG = ΔGo + R*T*ln Q

As Q increases, R*T*ln Q would increase and hence ΔG would increase.

So, it becomes less spontaneous

Answer: A