you want me to count and tell ah?? lemme tell you just the approach for the mono chlorinated product first for in pentane it can be 1 chloropentane or 2 chloro pentane and 3 chloro pentane and then we have to consider diff constitutional isomers of pentane itself like 2 methyl butane and 2,2 dimethyl propane and substitute similar chlorine in diff positions seing differentiation

 

approach in a similar way for hexane!!!