Mallika, you haven't mentioned which stream in B.Sc do you want to pursue. Ideally for pursuing B.Sc or any other course for that matter, you should have completed your 12th and passed in all subjects. In addition, your marks sheet should mention as "Passed". If your result shows Failed, then you have to appear for Chemistry paper, clear the exam and then pursue B.Sc. You cannot move on to next course without clearing or passing the current level.