Chemistry just involves slight understanding, numerical and organic are direct from NCERT. Getting 70/70 in chemistry is not a big deal. If u know all the topics well and if you had enough practice then you can easily get 70.
- Read and practice NCERT thoroughly. Each and every example of organic and each of the inorganic reactions you have to remember
- Don't leave any equation of NCERT in organic as well as inorganic. They can ask one equation in 10 different ways, so know every aspect of a particular equation.
- For reasoning type organic questions you should have to write accurate reasons and please use a suitable diagram to explain it. While solving inorganic reasoning questions you should give proper reasons.
- Practice is the key to excellence. One must practice ten years question paper as most of the questions are repeated in CBSE board exams. Go through last 10 year papers available at https://www.qb365.in/materials as its the max. that a variation pattern is observed in question.