Question

question 9 of 25 which of the following reactions would result in increased entropy? a. kno3(s)→k+(aq)+no3-(aq) b. 2co(g)+o2(g)→2co2(g) c. 2co(g)+2no(g)→2co2(g)+n2(g) d. n2(g)+3h2(g)→2nh3(g)

Explanation:

Step1: Recall entropy concept

Entropy increases when number of moles of gas increases or when a solid becomes aqueous or gas.

Step2: Analyze option A

A solid ($KNO_3$) dissociates into aqueous ions. Entropy increases as particles are more dispersed in solution.

Step3: Analyze option B

3 moles of gas (2 of $CO$ and 1 of $O_2$) form 2 moles of gas ($CO_2$). Entropy decreases.

Step4: Analyze option C

4 moles of gas (2 of $CO$ and 2 of $NO$) form 3 moles of gas (2 of $CO_2$ and 1 of $N_2$). Entropy decreases.

Step5: Analyze option D

4 moles of gas (1 of $N_2$ and 3 of $H_2$) form 2 moles of gas ($NH_3$). Entropy decreases.

Answer:

A. $KNO_3(s)
ightarrow K^+(aq)+NO_3^-(aq)$