Can i put the submitted paper in the arxiv?
If you have just submitted the paper, chances are you haven't given the rights over to the committee. As long as you haven't agreed to some terms and conditions that gives temporary ownership to the conference, then you should still have ownership of the paper and can do what you want with it. 

If you want to be doubly sure, a short email to the conference proceedings editor can erase any doubt you may have.