Preparing for competitive exams like IIT JEE, WB JEE, and NEET requires a solid foundation in chemistry and relentless practice. This book, "20,000+ Chemistry MCQs for IIT JEE, WB JEE, and NEET with Solutions," is designed to be an invaluable resource for students aiming to excel in these challenging examinations. In this comprehensive practice book, I have compiled over 20,000 meticulously selected multiple-choice questions, each crafted to test and enhance your understanding of chemistry concepts. These questions cover a wide range of topics, ensuring that you are well-prepared for every aspect of the syllabus. The detailed solutions provided for each question not only clarify the correct answers but also explain the underlying principles, helping you to grasp the concepts more effectively. This book is the culmination of years of teaching, research, and interaction with students at various levels of education. It reflects the challenges faced by students and aims to address them through targeted practice and clear explanations. The questions range from fundamental to advanced levels, allowing you to progressively build your knowledge and confidence. Whether you are beginning your preparation or looking to fine-tune your skills, this book is structured to meet your needs. The practice problems are designed to simulate the exam environment, helping you to develop the time management and problem-solving skills essential for success. I am confident that this book will serve as a valuable tool in your preparation journey. I encourage you to approach each question with curiosity and determination, and to use the solutions as a learning tool to deepen your understanding. With diligent practice and a strong grasp of the concepts, you will be well- equipped to achieve your academic goals. Wishing you all the best in your studies and future endeavors.