Đáp án:
\(\begin{array}{l}
a)\\
CTHH:{C_2}{H_6}\\
b)\\
{N_C} = 6 \times {10^{23}}\text{(Nguyên tử)}\\
{N_H} = 18 \times {10^{23}}\text{(Nguyên tử)}
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a)\\
CTHH\,A:{C_x}{H_y}\\
\% C = \dfrac{{x{M_C}}}{{{M_A}}} \times 100\% = \dfrac{{12x}}{{30}} \times 100\% = 80\% \\
\Rightarrow x = \dfrac{{30 \times 0,8}}{{12}} = 2\\
{M_A} = 2{M_C} + y{M_H} = 30\\
\Rightarrow y = 30 - 24 = 6\\
\Rightarrow CTHH:{C_2}{H_6}\\
b)\\
{n_{{C_2}{H_6}}} = \dfrac{V}{{22,4}} = \dfrac{{11,2}}{{22,4}} = 0,5mol\\
{n_C} = 2{n_{{C_2}{H_6}}} = 1mol\\
{N_C} = n \times {N_A} = 1 \times 6 \times {10^{23}} = 6 \times {10^{23}}\text{(Nguyên tử)}\\
{n_H} = 6{n_{{C_2}{H_6}}} = 3mol\\
{N_H} = n \times {N_A} = 3 \times 6 \times {10^{23}} = 18 \times {10^{23}}\text{(Nguyên tử)}
\end{array}\)
