Question

Prin incalziea in prezenta de nichel a unui amestec de C2H4 si H2 in raport molar 1:2 , se obtine un amestec gazos cu densitatea fata de aer =0,5272.Randamentul reactiei este : R90 %

Answer 1

Avem raport de 1:2 => putem lua 1 mol etena si 2moli H2, caci nu ne intereseaza ce cantitate e exact.
consideram ca x moli de etena se hidrogeneaza pana la etan
1mol...1mol...1mol
C2H4 + H2 -> C2H6
x...........x.........x
1mol.1mol
H2 -> H2
2-x....2-x
1mol......1mol
C2H4 -> C2H4
1-x moli...1-x moli
namestecfinal=3-x moli
daer=Mamestec/Maer => Mamestec=0,5272*28,9=15,23608 g/mol
aplicam formula M amestecului
15,23608=[30(x)+2(2-x)+28(1-x)]/(3-x)
45,70824-15,23608x=30x+4-2x+28-28x
45,70824-15,23608x=32
15,23608x=13,70824 => x≈0,9 moli
randament=npractic*100/nteoretic=0,9*100/1=90%