Ответ:
дано
V(C2H5OH) = 20.7 mL
W(C2H5OH) = 96%
p(C2H5OH) = 0.8 g/mL
η(C2H5OH) = 90%
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m(C6H12O6)-?
C6H12O6-->2C2H5OH+2CO2
m(C2H5OH) = V(C2H5OH)*W(C2H5OH)*p(C2H5OH) / 100% = 20.7 * 96% * 0.8 / 100% = 15.9 g
m(C2H5OH) = 15.9 * 100% / 90% = 17.67 g
M(C2H5OH) = 46 g/mol
n(C2H5OH) = m/M = 17.67 / 46 = 0.38 mol
n(C6H12O6) = 2n(C2H5OH)
n(C6H12O6) = 0.38 / 2 = 0.19 mol
M(C6H12O6) = 180 g/mol
m(C6H12O6) = n*M = 0.19 * 180 = 34.2 g
ответ 34.2 г
Объяснение: