Răspuns :
-calculez masa de alcool, din densitate
ro=m/v---> m= 700mlx0,79g/ml= 553galcool
-calculez moli alcool,stiind M,C2H6O= 46g/mol
niu= m/M=553/46--> 12mol
-calculez moli si volum etena cu randament 100% si in c.n,
1mol......................................1mol
CH3-CH2OH ------------> CH2=CH2 + H2O
12mol........................................niu= 12mol etena
V=niuxVm= 12x22,4 l=269 l este volum teoretic in c.n.
-calculez volumul si moli practic , cu randament 80%
80/100= Vpr/269-------> Vpr=215,2 L
niu= V/Vm= 215,2/22,4 mol=9,6 mol etena
-calculez volumul de etena in conditiile date
pV= nRT---> 2xV= 9,6X0,082X(273+27)...............................CALCULEAZA V !!!