CBSE: Check important extra questions for the upcoming CBSE Class 9 Science exam 2020-21 from Chapter 3 (Atoms & Molecules) of Class 9 Science NCERT textbook. Answers of all the questions are also ...
6.Calculate the number of moles of magnesium present in a magnesium ribbon weighing 12 gm. Molar atomic mass of Magnesium is 24 gm/mol. 7.Write postulates of Daltion's atomic theory (at least three).