A - 7g N 2

B - 2g H 2

C - 16g NO 2

D - 16g O 2

 

Answer

B - 2g H 2

 

Explanation: 

Number of moles = Given mass of substance / Molecular mass of substance 

                        n  = m / M

                 

7g N 2 → 7 / 28 = 0.25 moles of molecules

2g H 2 → 2 / 2 = 1 mole of molecules

16g NO 2 → 16 / 46 = 0.347 moles of molecules

16g O 2 → 16 / 32 = 0.5 moles of molecules

 

Thus 2g H 2 has the most number of molecules.

  1. Class 9
  2. Chapter 3 Class 9 - Atoms And Molecules (Term 2)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo