Răspuns:
M,CH4=16g/mol
M,C2H6=30g/mol
M,C3H8=44g/mol
amestecul este format din a moli Ch4, b moli C2H6 c moli cC3H8
a: b: c= 1:2:3----> b=2a c=3a
16a+30b+44c=416
208a=416----> a=2mol b= 4mol c= 6mol
416g amestec....2x16gCH4....4molx30gC2H6......6molX44C3H8
100G.................................X........................Y............................Z
X= 7,7% CH4
Y=28,8% C2H6
Z=63,5%C3H8
Explicație: