here is class 9th CBSE science all in one book by Arihant it is the best book available in the market for science it contains complete theory with solved examples

it includes
1) assertion reason
2) case base question
3) NCERT question
4) proper summary
5) some Challenger question
6) NTSE Olympiad question
7) exam practice and science Olympiad question

if you want to clear your concepts in depth and want to achieve a good knowledge and achieve a good marks in your exams you can refer to this book