дано
V(CO2) = 2.8 L
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m(HCL)-?
m(CaCO3)-?
2HCL+CaCO3-->CaCL2+H2O+CO2
n(CO2) = V(CO2) / Vm = 2.8 / 22.4 = 0.125 mol
n(CO2) = n(CaCO3) = 0.125 mol
M(CaCO3) = 100 g/mol
m(CaCO3) = n*M = 0.125 * 100 = 12.5 g
2n(HCL) = n(CO2)
n(HCL) = 2*0.125 = 0.25 mol
M(HCL) = 36.5 g/mol
m(HCL) = n*M = 0.25 * 36.5 = 9.125 g
ответ 9.125 г, 12.5 г