Дано
m(CH3OH) = 12 g
m(CH3COOH) = 10 g
m практ(CH3COOCH3) = 18.5 g
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η(CH3COOCH3)-?
M(CH3COH) = 44 g/mol
n(CH3COH) = m/M = 12/44 = 0.27 mol
M(CH3COOH) = 60 g/mol
n(CH3COOH) = m/M = 10/60 = 0.17 mol
n(CH3OH)>n(CH3COOH)
M(CH3COOCH3)= 74 g/mol
10 Xg
CH3COOH+CH3OH-->CH3COOCH3+H2O
60 74
X = 10*74 / 60 = 12.33 g
η = 12.33 / 18.5 * 100% = 66.65%
ответ 66.65%