Đáp án:
\({{\text{V}}_{dd\;{{\text{H}}_2}S{O_4}}} = 107,46{\text{ ml}}\)
Giải thích các bước giải:
Phản ứng xảy ra:
\(N{a_2}O + {H_2}O\xrightarrow{{}}2NaOH\)
\({n_{N{a_2}O}} = \frac{{15,5}}{{23.2 + 16}} = 0,25{\text{ mol}} \to {n_{NaOH}} = 2{n_{N{a_2}O}} = 0,5{\text{ mol}}\)
Trung hòa dung dịch trên
\(2NaOH + {H_2}S{O_4}\xrightarrow{{}}N{a_2}S{O_4} + 2{H_2}O\)
\( \to {n_{{H_2}S{O_4}}} = \frac{1}{2}{n_{NaOH}} = 0,25{\text{ mol}} \to {{\text{m}}_{{H_2}S{O_4}}} = 0,25.98 = 24,5{\text{ gam}} \to {{\text{m}}_{dd{\text{ }}{{\text{H}}_2}S{O_4}}} = \frac{{24,5}}{{20\% }} = 122,5{\text{ gam}} \to {{\text{V}}_{dd\;{{\text{H}}_2}S{O_4}}} = \frac{{122,5}}{{1,14}} = 107,46{\text{ ml}}\)
Ta có:
\({n_{N{a_2}S{O_4}}} = {n_{{H_2}S{O_4}}} = 0,25{\text{ mol}} \to {{\text{C}}_{M{\text{ N}}{{\text{a}}_2}S{O_4}}} = \frac{{0,25}}{{0,15}} = 1,67M\)
