дан

m(CaO) = 140 kg

m практ (Ca(OH)2) = 182 kg

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η(Ca(OH)2)-?

CaO+2H2O--->Ca(OH)2

M(CaO) = 56 kg/kmol

n(CaO) = m/M = 140 / 56 = 2.5  kmol

n(CaO) = n(Ca(OH)2) = 2.5 kmol

M(Ca(OH)2) = 74 kg/kmol

m теор(Ca(OH)2) = n*M = 2.5 * 74 = 185 kg

η(Ca(OH)2) = m практ  (Ca(OH)2) /mтеор (Ca(OH)2) * 100% = 182 / 185 * 100% = 98.4%

ответ 98.4%