Question

How to fjnd number of monochloro derivatives?

Answer 1

Answer:

You can get 5 monochloro derivative of n-pentane. The structure of n-pentane is somewhat like this CH3-CH2-CH2-CH2-CH3. Monochloro derivatives means C-12 sharing at least and at most one chlorine bond. In an alkane every C atom can have at least and at most one chlorine bond.

Answer 2

Brute force. You have to look to see how replacing each H with a Cl gives a different compound. Thus there is only one chloromethane or chloroethane, but there are two chloropropanes or chlorobutanes, and three chloropentanes.