Question

un amestec de propena si 2 butena in raport molar 1 :2 se oxideaza cu KMnO4 /H plus , formand o substanta care se dizolva in 470 g apa rezultand o solutie de concentratie 6 % . Calculati masa de propena din amestecul dat .

Answer 1

1mol................................60g
CH2=CH-CH3 + 5[O] -> CH3-COOH + CO2 + H2O
xmoli...............................60x
1mol.....................................2*60g
CH3-CH=CH-CH3 + 4[O] -> 2CH3-COOH
2x.........................................240x
macid=md=300x
ms=md+mapa=300x+470g
aplicam formula concentratiei
6/100=300x/(300x+470)
1800x+2820=30000x
28200x=2820 => x=0,1moli
n=m/M
mpropena=n*Mpropena=0,1*42=4,2g propena