Question

Consider a process in which a solid decomposes at room temperature to form a solid and a gas. in addition, a beaker containing this solid will feel warm to the touch as the reaction occurs.

for this process at room temperature,ΔG is ____,ΔS is ____, and ΔH is ____.
a. negative/positive/positive
b. negative/negative/negative
c. negative/positive/negative
d. positive/positive/positive
e. positive/positive/negative

Answer 1

The correct answer is (c) negative/positive/negative. For a solid decomposing into another solid and a gas that releases heat, ΔG is negative, ΔS is positive, and ΔH is negative.

Step-by-step explanation:

If a solid decomposes at room temperature into another solid and a gas, and the beaker feels warm, we know the reaction is exothermic (ΔH is negative because heat is released). Because the reaction produces a gas from a solid, there is an increase in entropy (ΔS is positive). Since the solid feels warm to the touch as the reaction occurs, this indicates that the reaction is spontaneous at room temperature, suggesting that the Gibbs free energy (ΔG) is negative. Therefore, for this process at room temperature, ΔG is negative, ΔS is positive, and ΔH is negative. The correct answer is (c) negative/positive/negative.

The process described in the question involves the decomposition of a solid at room temperature to form a solid and a gas. Since the process generates heat and the reaction is spontaneous, the change in Gibbs free energy (ΔG) is negative. Therefore, option c. negative/positive/negative is the correct answer choice.