Дано
m = 190 г
w(HCl) = 5% = 0.05
Решение
m(HCl) = mw(HCl) = 190 * 0.05 = 9.5 г
n(HCl) = m(HCl) / M(HCl) = 9.5 / (1 + 35.5) = 9.5 / 36.5 = 0.26 моль
ZnO + 2HCl = ZnCl2 + H2O
n(ZnCl2) = 0.5n(HCl) = 0.5 * 0.26 = 0.13 моль
m(ZnCl2) = n(ZnCl2)M(ZnCl2) = 0.13 * (65 + 2 * 35.5) = 0.13 * 136 = 17.68 г
Ответ: 17.68 г