Question

As NH4Cl dissolves in water, and cools the solution,

a. delta H is negative, and delta S is negative
b. delta H is positive, and delta S is negative
c. delta H is negative, and delta S is positive
d. delta H is positive, and delta S is positive

Answer 1

d. delta H is positive, and delta S is positive

Step-by-step explanation:

The process of dissolution of NH4Cl is:

NH4Cl(s) → NH4+(aq) + Cl-(aq)

As the solution is cooled, the process is absorbing energy, that means ΔH > 0. (ΔH < 0 when the heat is released).

As there are produced 2 ions from 1 solid molecule, the disorder is increasing and ΔS > 0

The right answer is:

d. delta H is positive, and delta S is positive