Em tham khảo nha :
\(\begin{array}{l}
1)\\
a)\\
Mg + {H_2}S{O_4} \to MgS{O_4} + {H_2}O\\
b)\\
{m_{{H_2}S{O_4}}} = \dfrac{{196 \times 15}}{{100}} = 29,4g\\
{n_{{H_2}S{O_4}}} = \dfrac{{29,4}}{{98}} = 0,3mol\\
{n_{Mg}} = {n_{{H_2}S{O_4}}} = 0,3mol\\
{m_{Mg}} = 0,3 \times 24 = 7,2g\\
c)\\
{n_{{H_2}}} = {n_{{H_2}S{O_4}}} = 0,3mol\\
{V_{{H_2}}} = 0,3 \times 22,4 = 6,72l\\
2)\\
a)\\
{K_2}O + {H_2}S{O_4} \to {K_2}S{O_4} + {H_2}O\\
{m_{{H_2}S{O_4}}} = \dfrac{{196 \times 12}}{{100}} = 23,52g\\
{n_{{H_2}S{O_4}}} = \dfrac{{23,52}}{{98}} = 0,24mol\\
{n_{{K_2}O}} = {n_{{H_2}S{O_4}}} = 0,24mol\\
{m_{{K_2}O}} = 0,24 \times 94 = 22,56g\\
{n_{{K_2}S{O_4}}} = {n_{{H_2}S{O_4}}} = 0,24mol\\
{m_{{K_2}S{O_4}}} = 0,24 \times 174 = 41,76g
\end{array}\)
