Дано:
m (C2H5OH) = 13,8г
m (CuO) = 28г
m (CH3CHO) = 9,24г
W () - ?
C2H5OH + CuO = CH3CHO + Cu + H2O
n=1моль⠀n=1моль⠀n=1моль
M=46г/м⠀М=80г/м⠀M=44г/м
1) n (C2H5OH) = 13,8/46 = 0,3моль
2) n (CuO) = 0,35моль
3) n (CuO) > n (C2H5OH) => CuO в избытке
4) n (CH3CHO) = n (C2H5OH) = 0,3моль
5) m (CH3CHO) = 44*0,3 = 13,2г
6) W (CH3CHO) = 9,24/13,2*100% = 70%
Ответ: W (CH3CHO) = 70%
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