Question

Which substance increases in solubility as the temperature decreases?

Answer 1

NH₃ would.  This is because of the fact that ammonia is a molecular gas while the other options are ionic crystals.  Crystals increase in solubility when the temperature increases while gases increase in solubility while temperatures deceases.

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Answer 2

Answer:

The correct answer is 2.

Explanation:

The NH3 solubility curve shows that when the temperature increases, the solubility of the compound decreases. The molecule is not flat but has a tetrahedral shape with a vacant vertex, and this is due to the formation of hybrid sp³ orbitals. Unlike other compounds, the NH3 solubility curve has been experimentally tested and is attached for better understanding.

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