Is it okay to email the general/conference chairs if I feel the reviews are biased and unprofessional? In a conference with an author rebuttal phase, I received a review from a reviewer (who gave a strong reject) asking to compare my work to a paper which is not even on the same problem as my paper. I firmly believe that this review is biased and the reviewer is either the author of the paper, which he/she is asking me to compare or was planning  to putting a similar paper.
Is it okay to email the chairs to look into my paper and reviews?
This situation happens many times in conferences. At least, I have experienced once.


  I firmly believe that these reviews are biased and the reviewer is either the author of the paper, which he/she is asking me to compare or was planning to put a similar paper. 


This is a straight-forward assumption. And, I think you are misinterpreting in this aspect. Though it could be true, you are thinking too much about the rejection.


  Is it okay to email the chairs to look into my paper and reviews?


Since this is rebuttal phase, this might not sound okay to email at this point. Just write the rebuttal and/or do the revision.

I feel you are too much emotionally attached to the paper and that is how you are assessing the situation. Take a break from this paper. Look at the review after few days, and think positive.

"Rejections are good times of research, in which we learn to accept the truth."