for 11th standard most effective and possible way is
besides school and coaching hour you should give 4-5 hour in your home for IIT JEE Prepration.
and for the rest of your board subject except(P C M) you can give 1 hour per day and 3-4 day in week.
I will suggest you to start from the begning. first revise your old notes in the same order as you was tought in coaching.
also refer good books of that topic. then solve standard question from books and IIT study material
and after finish the topic solve question of that topic from previous IIT JEE papers.
Just stay calm and focus on understanding rather than mugging. Be regular in class and stay with concepts.
O P Tandon and P bahadur is Recomended for physical chemistry
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