Since halogenation of alkanes is mostly uncontrolled, you are likely to get a mixture of mono and polysubstituted products. These will be-
Monosubstituted: 1
Disubstituted: 2
Trisubstituted: 2
Tetrasubstituted: 2
Pentasubstituted: 1
Hexasubstituted: 1
Thus, you get a total of 9 structural isomers.
C2H6(g) +Br2(l) --> C2H5Br(l) +HBr(g).
C2H6(g) +Br2(l) --> C2H4Br(l) +2HBr(g).
C2H6(g) +2Br2(l) --> C2H2(l) +4HBr(g).
C2H6(g) +3Br2(l) --> C2H3Br3(l) +3HBr(g).
C2H6(g) +Br2(l) --> CHBr(l) +HBr(g)+ CH4
C2H6(g) +4Br2(l) --> C2H5Br(l) + HBr(g) + 3Br2
C2H6(g) +2Br2(l) + H2 --> C2H5Br(l) +3HBr(g).
2C2H6(g) +Br2(l) --> C2H5Br(l) + HBr(g) + C2H6
C2H6(g) +3Br2(l) --> C2HBr(l) +5HBr(g).