NaCl + AgNO3 \( \to \) AgCl\( \downarrow \) + NaNO3
x mol x mol
KCl + AgNO3 \( \to \) AgCl\( \downarrow \) + KNO3
y mol y mol
\(\left\{ \begin{array}{l}58,5{\rm{x}} + 74,5y = 0,887(1)\\143,5{\rm{x}} + 143,5y = 1,913(2)\end{array} \right.\)
\( \Leftrightarrow \left\{ \begin{array}{l}143,5{\rm{x}} + 182,7y = 2,176\\143,5{\rm{x}} + 143,5y = 1,913\end{array} \right. \Rightarrow y = {6,71.10^{ - 3}}mol\)
Khối lượng KCl là : \({74,5.6,71.10^{ - 3}} = 0,5(g)KCl\)
\(\% {m_{KCl}} = \dfrac{{0,5}}{{0,887}}.100\% = 56,4\% \)
\( \Rightarrow \% {m_{NaCl}} = 43,6\% \)
