Đáp án:

\(\% {m_{{N_2}}} = \)19,13%

Giải thích các bước giải:

\(\begin{array}{l}
\dfrac{{{V_{{N_2}}}}}{{{V_{C{l_2}}}}} = \dfrac{3}{5} \to \dfrac{{{n_{{N_2}}}}}{{{n_{C{l_2}}}}} = \dfrac{3}{5}\\
 \to {n_{C{l_2}}} = \dfrac{5}{3}{n_{{N_2}}}\\
\% {m_{{N_2}}} = \dfrac{{{m_{{N_2}}}}}{{{m_{{N_2}}} + {m_{C{l_2}}}}} \times 100\%  = \dfrac{{28{n_{{N_2}}}}}{{28{n_{{N_2}}} + 71 \times \dfrac{5}{3}{n_{{N_2}}}}} \times 100\%  = 19,13\% 
\end{array}\)

$Đáp$ $án$ $+$ $Giải$ $thích$ $các$ $bước$ $giải$ $:$

$\frac{V_{N_2}}{V_{Cl_2}}$ $=$ $\frac{3}{5}$

$⇒$ $\frac{n_{N_2}}{n_{Cl_2}}$ $=$ $\frac{3}{5}$

$⇒$ $\frac{m_{N_2}}{m_{Cl_2}}$ $=$ $\frac{3×28}{5×35,5}$ $=$ $\frac{168}{355}$ 

$⇒$ $C$%$_{m_{Cl_2}}$ $=$ $\frac{355}{168+355}×100$% $≈$ $67,88$% 

$Chúc$ $bn$ $hk$ $tốt$ $!!$ $:))))$

$Xin$ $ctlhn$ $ạ.$