In order to solve chemistry questions in competitive level exam make sure your concepts are clear. You can take help of NCERT books for your practice. 

Apart, from NCERT you can refer below recommended books for your preparation

Morrison & Boyd

J.D. Lee

R. C. Mukerjee

P.Bahadur

P.W.Atkins

It is recommended to refer previous year papers to understand the type of uestions asked in the exam and solve as much as MCQs for your practice.

You can also solve mock test series as well to analyse your preparation level at regular interval of time and to know your strength and weakness. 

Good luck!!