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Interpreting Reactions

APCHEM-4YS476

Consider the reaction depicted below.

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Also, consider these data concerning the reaction.

Property Value
$\Delta H^{\circ}_{solution}$ -30 kJ/mol NH$_3$
$\Delta S^{\circ}_{solution}$ -70 J/mol$\cdot$K
Molar Solubility (25$^{\circ}$C) 15 M

$\ $
Which of the following does NOT provide a reasonable description of this system?

A

The process can be represented by the equation:

$$N{ H }_{ 3 }(aq)+{ H }_{ 2 }O(l)\rightleftharpoons N{ H }_{ 4 }^{ + }(aq)+O{ H }^{ – }(aq)$$

B

As the temperature of the system is raised, the pH will decrease because an increase in temperature favors the endothermic direction in an equilibrium system. In this system, the endothermic direction favors reactants.

C

As the temperature of the system is raised, the solubility of ammonia gas will increase, increasing the quantity of hydroxide ion in solution.

D

As the temperature of the system increases, the dissolving process will become less thermodynamically favored.