дано
m(NH3) = 10.2 g
m(HCL) = 14.6 g
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m(NH4CL)-?
M(NH3) = 17 g/mol
n(NH3) = m/M = 10.2 / 17 = 0.6 mol
M(HCL) = 36.5 g/mol
n(HCL) = m/M = 14.6 / 36.5 = 0.4 mol
n(NH3)> n(HCL)
NH3+HCL-->NH4CL
n(HCL) = n(NH4CL) = 0.4 mol
M(NH4CL) = 53.5 g/mol
m(NH4CL) = n*M = 0.4 * 53.5 = 21.4 g
ответ 21.4 г