Em tham khảo nha:

\(\begin{array}{l}
4)\\
{n_{C{H_4}}} = \dfrac{A}{N} = \dfrac{{9 \times {{10}^{23}}}}{{6 \times {{10}^{23}}}} = 1,5\,mol\\
{m_{C{H_4}}} = n \times M = 1,5 \times 16 = 24g\\
{V_{C{H_4}}} = n \times 22,4 = 1,5 \times 22,4 = 33,6l\\
{n_{S{O_2}}} = \dfrac{V}{{22,4}} = \dfrac{{6,72}}{{22,4}} = 0,3\,mol\\
{m_{S{O_2}}} = n \times M = 0,3 \times 64 = 19,2g\\
A = n \times N = 0,3 \times 6 \times {10^{23}} = 1,8 \times {10^{23}}\\
5)\\
a)\\
{C_2}{H_4} + 3{O_2} \xrightarrow{t^0} 2C{O_2} + 2{H_2}O\\
b)\\
{n_{{C_2}{H_4}}} = \dfrac{m}{M} = \dfrac{{14}}{{28}} = 0,5\,mol\\
{n_{{O_2}}} = 3{n_{{C_2}{H_4}}} = 1,5\,mol\\
{V_{{O_2}}} = 1,5 \times 22,4 = 33,6l\\
c)\\
{n_{C{O_2}}} = 2{n_{{C_2}{H_4}}} = 1\,mol\\
{m_{C{O_2}}} = n \times M = 1 \times 44 = 44g
\end{array}\)