дано

m(CaCO3) = 200 g

m(NaOH)= 80 g

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m(NaHCO3)-?

CaCO3+2HCL-->CaCL2+H2O+CO2

M(CaCO3) = 100 g/mol

n(CaCO3) = m/M = 200 / 100 = 2 mol

n(CaCO3)= n(CO2) = 2 mol

CO2+NaOH-->NaHCO3

n(CO2) = n(NaHCO3) = 2 mol

M(NaHCO3) = 84 g/mol

m(NaHCO3) = n*M = 2* 84 = 164 g

ответ 164 г