In three moles of ethane` (C_(2)H_(6))`, calculate the following:
(i) Number of moles of carbon atoms.
(ii) Number of moles of hydrogen atoms.`
(iii) Number of molecules of ethane.

Explanation

(i) 1 mole of ethane contains 2 moles of carbon atoms.
`therefore` Number of moles of carbon atoms in 3 moles of ethane `=3 xx 2=6`
(ii) 1 mole of ethane contains 6 moles of hydrogen atoms.
`therefore` Number of moles of hydrogen atoms in 3 moles of ethane `= 3 xx 6 = 18`
(iii) 1 mole of ethane contains `6.022 xx 10^23` (Avogadro.s no.) molecules.
`therefore` Number of molecules in 3 moles of ethane
`= 3 xx 6.022 xx 10^(23)`
`=18.066 xx 10^(23)`