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Arrange the following in the order asked.
Increasing order of solubility in water: , , .
Increasing order of solubility in water:
$\text{C}_6\text{H}_5\text{NH}_2$, $(\text{C}_2\text{H}_5)_2\text{NH}$, $\text{C}_2\text{H}_5\text{NH}_2$.
Answer
Answer
AIOrder, first to last: C6H5NH2, (C2H5)2NH, C2H5NH2
$\mathrm{C_6H_5NH_2} < (\mathrm{C_2H_5})_2\mathrm{NH} < \mathrm{C_2H_5NH_2}$
Because the large hydrophobic phenyl group reduces hydrogen bonding most, and the primary amine with two N-H bonds forms more hydrogen bonds with water than the secondary amine.
From ISC 2018 Specimen Chemistry Paper 1, question 14(c).