m(HCl) = 50*14.6% = 7.3g
反应方程式：
2HCl + Na2CO3 == 2NaCl + H2O + CO2↑
73 106 117 44
7.3g m1 m2 m3
73/7.3 = 106/m1 = 117/m2 = 44/m3
得m1 = 10.6g,m2 = 11.7g,m3 = 4.4g
所以混合物中NaCl的质量 = 23.9 - 10.6 = 13.3g
反应后生成的溶液中NaCl质量 = 11.7+13.3 = 25g
溶液的质量 = 23.9+50-4.4 = 69.5g
溶液的质量分数 = 25/69.5 = 36%