Class 12 Inorganic Chemistry. The most conceptual chapter here is co-ordination compounds. A lot of questions are asked and it will also make d and f block easier for you to remember. The greater part of p-Block is also in Class 12.  

A lot of students who find chapters like p-block difficult, are weak in chemical bonding and I recommend you read it from my Class 11 Notes. These notes will give you a whole new perspective to these chapters, and help in learning the complex orders.

The chapters on p-Block, d and f block and environmental chemistry include important points from NCERT and you can go through them once from the NCERT as well. 

The notes are organized as follows:

1.  Co-ordination Compounds
2.  Oxy-Acids 
3.  p-Block
4.  d-Block and f-Block
5.  Environmental Chemistry

Pro-Tip: It is advisable to read Periodic Table and Chemical Bonding from my Class 11 Notes. Conceptually, co-ordination compounds and oxy-acids is must do from my Class 12 notes. Rest, NCERT reading would be good enough.

Thanks and credit is due to Sandeep Singh (SS sir) who was able to memorize a 14-page supplement on p-Block and recite it by heart in less than 30 minutes. A teacher going to that extent demonstrated to me that inorganic is a piece of cake if I give it my heart. A good teacher asks you to do something, a great teacher shows you how to do it.