a.

n SO3=$\frac{240}{80}$=3 mol

SO3+H2O→H2SO4

 3→               3             mol

CM H2SO4=$\frac{3}{2}$=1,5 M

b.

n HCl=$\frac{31,36}{22,4}$=1,4 mol

CM HCl=$\frac{1,4}{0,5}$=2,8 M

----------------Nguyễn Hoạt-----------------

a)

Ta có: \({n_{S{O_3}}} = \frac{{240}}{{80}} = 3{\text{ mol}}\)

\(S{O_3} + {H_2}O\xrightarrow{{}}{H_2}S{O_4}\)

\( \to {n_{{H_2}S{O_4}}} = {n_{S{O_3}}} = 3{\text{ mol}} \to {{\text{C}}_{M{\text{ }}{{\text{H}}_2}S{O_4}}} = \frac{3}{2} = 1,5M\)

b)

\({n_{HCl}} = \frac{{31,36}}{{22,4}} = 1,4{\text{ mol}} \to {{\text{C}}_{M{\text{ HCl}}}} = \frac{{1,4}}{{0,5}} = 2,8M\)