Em tham khảo nha:
\(\begin{array}{l}
a)\\
{N_{{H_2}O}} = n \times 6 \times {10^{23}} = 0,756 \times 6 \times {10^{23}} = 4,5 \times {10^{23}}\text{ phân tử}\\
b)\\
{N_{hh}} = (0,25 + 0,2) \times 6 \times {10^{23}} = 2,7 \times {10^{23}}\text{ phân tử}\\
c)\\
{n_{{H_2}S{O_4}}} = \dfrac{{9,8}}{{98}} = 0,1\,mol\\
{N_{{H_2}S{O_4}}} = 0,1 \times 6 \times {10^{23}} = 6 \times {10^{22}}\text{ phân tử}\\
d)\\
{n_{{H_2}}} = \dfrac{{2,24}}{{22,4}} = 0,1\,mol\\
{n_{C{O_2}}} = \dfrac{{4,48}}{{22,4}} = 0,2mol\\
{N_{hh}} = (0,1 + 0,2) \times 6 \times {10^{23}} = 1,8 \times {10^{23}}\text{ phân tử}
\end{array}\)
