дано
m(CxHyOz) = 3 g
V(CO2) = 2.24 L
m(H2O) = 1.8 g
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CxHyOz-?
n(C) = n(CO2) = V(CO2) / Vm = 2.24 / 22.4 = 0.1 mol
M(C) = 12 g/mol
m(C) = n*M = 0.1*12 = 1.2 g
n(H) = 2*n(H2O) =2* n(m/M) = 2*( 1.8 / 18 ) = 0.2 mol
M(H) = 1 g/mol
m(H) = n*M = 0.2 * 1 = 0.2 g
m(O) = m(CxHyOz) - (m(C)+m(H)) = 3 - (1.2 + 0.2) = 1.6 g
M(O) = 16 g/mol
n(O) = m/M = 1.6 / 16 = 0.1 mol
n(C) : n(H) : n(O) = 0.1 : 0.2 :0.1 = 1:2:1
C:H:O = 1:2:1
HCOH - формальдегид
ответ формальдегид