\textbf{95 --} \textbf{At equal temperature and concentration, upon dissolution of each of the following substances in water, the concentration of hydroxide ions decreases and the number of existing molecules in the solution increases the most?}
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(1) $\mathrm{NH_3(g)}$ \quad (2) $\mathrm{HCl(g)}$ \quad (3) $\mathrm{HCN(g)}$ \quad (4) $\mathrm{HCOOH(l)}$
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