Đáp án:
\( m = {m_{C{H_3}N{H_2}}}= 13,95{\text{ gam}}\)
Giải thích các bước giải:
Ta có:
\(CH_3N{H_2} + {H_2}S{O_4}\xrightarrow{{}}CH_3N{H_3}HS{O_4}\)
\(2CH_3N{H_2} + {H_2}S{O_4}\xrightarrow{{}}{(CH_3N{H_3})_2}S{O_4}\)
Ta có:
\({n_{{H_2}S{O_4}}} = 0,3.1 = 0,3{\text{ mol}}\)
Vì 2 muối có nồng độ bằng nhau nên số mol bằng nhau.
\( \to {n_{C{H_4}N{H_3}HS{O_4}}} = {n_{{{(C{H_3}N{H_3})}_2}S{O_4}}} = \frac{{0,3}}{2} = 0,15{\text{ mol}}\)
\( \to {n_{C{H_3}N{H_2}}} = {n_{C{H_3}N{H_3}HS{O_4}}} + 2{n_{{{(C{H_3}N{H_3})}_2}S{O_4}}}\)
\( = 0,15 + 0,15.2 = 0,45{\text{ mol}}\)
\( \to m = {m_{C{H_3}N{H_2}}} = 0,45.31 = 13,95{\text{ gam}}\)
