dear anuj shrivastava
carbon does not make four bond with another carbon because it is very impossible to arrange four bonds in the space, so they can repel each other very less, because there are only three axis. and the catinaton property of carbon will also get vanish if it made four bonds.
Please feel free to post as many doubts on our discussion forum as you can. We are all IITians and here to help you in your IIT JEE preparation.
Win exciting gifts by answering the questions on Discussion Forum..
ALL THE BEST
REGARD
DEEPAK KUMAR SINGH