Question

In three moles of ethane (C2H6), calculate the following :(i) Number of moles of carbon atoms.(ii) Number of moles of hydrogen atoms.(iii) Number of molecules of ethane.Ncert solutions for Class 11th Chemistry Part - 1 Chapter 1 Exercise 9

Answer 1

I) One mole of ethane contains 2 carbon atoms 
so 3 moles of ethane contains 6 mole of carbon atoms.
II) One mole of ethane contains 6 hydrogen atoms 
so 3 moles of ethane contains 18 mole of hydrogen atoms.
III) One mole of ethane contains 6.023×10²³ molecules of ethane
so 3 mole of ethane contains 3×6.023×10²³ =18.069 ×10²³=1.8069 ×10²²  molecules of ethane..... 
hope it helps………….