niu= 179,2l/22,4l/mol= 8mol metan
CH4 +Cl2 --> CH3CL +HCl 3X
CH4 +2cl2--->CH2Cl2 +2HCl 2X
CH4----------------->CH4 2X
3X+2X+2X=8---> X=1,14MOL
IN prima ecuatie, 1mol metan......1molCl2
3x1,14...............3,x1,14
in a doua ecuatie 1mol metan........2mol Cl2
2x,1,14.............4x1,14
total: 7x1,14mol clor-->7,98mol clor---> V=7.98molx22,4l/mol calculeaza !!!!