Дано
m(C2H6)=10 g
m(практC2H5OH)=120 g
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η-?
C2H6-->C2H4+H2
C2H4+H2O-->C2H5OH
M(C2H6)=30 g/mol
n(C2H6)=m/M=84/30=2.8 mol
n(C2H6)=n(C2H5OH)=2.8 mol
M(C2H5OH)=46 g/mol
m(теор C2H5OH)=n*M=2.8*46= 128.8 g
η=m(практ)/m(теор)*100%=120/128.8*100%
η=93.17%
ответ 93.17%