Ans: There are separate books for Organic Chemistry, Inorganic Chemistry, Analytical Chemistry, Practical Chemistry and Biochemistry. You can refer to books like Organic Chemistry, 6th Edition by Morrison & Boyd, Concise Inorganic Chemistry, 5th Edition by Lee (published by ELBS with Chapman & Hall), Analytical Chemistry, 5th Edition by Christian(published by John Wiley & Sons Inc). These suggested books contain complete theory and practical problems exactly on the INChO exam pattern as well as NSEC exam pattern. You will find ample number of solved examples devised as per the level and pattern of the Indian National Olympiads. Check Vedantu.com for further information on INCho olympiad exam pattern and structure 2020.