Is it possible to mine alt coins on a CPU? I know its pointless to mine bitcoin on a CPU but are alt coins any different?
It is definitely possible.
It is usually not especially profitable, if at all. This depends on what CPU, what coin, power costs, etc. At current rates, expect <$1/day, even for a high-end CPU.
There's several threads in this subforum on the best CPU coins to mine right now, but I still wouldn't recommend it if your goal is to make money at a reasonable rate.