The NCERT Class 11 Chapter 3, Classification of Elements and Periodicity in Properties belongs to unit 2 of the NCERT syllabus. For the class 11 year-end exam, unit 1 and unit 3 when combined together carries a massive weightage of 11 marks. Through this chapter, students get to learn about the development cycle of the Periodic Table and the Periodic Law. This chapter is considered extremely important by the experts as it covers concepts important to class 11 as well as class 12, along with the NEET and JEE exams.