Answers

2016-02-12T08:38:54+05:30
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 ×10
²²  molecules of ethane..... 
hope it helps………….
1 5 1