дано
m(CH3-CH2-CH2-COOH) = 120 g
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m(CH3CH2CH2COH)-?
X g 120 g
CH3 - CH2-C-H2-COH+Ag2O-->2Ag+CH3-CH2-CH2-COOH
72 g/mol 88 g/mol
M(CH3CH2CH2COOH) = 88 g/mol
M(CH3-CH2-CH2-COH) = 72 g/mol
X = 72*120 / 88 = 98.18 g
ответ 98.18 г