Describe how to convert between mass and the number of moles of a substance.

mass= no.of atoms present× atomic mass

no. of moles=given mass÷molar mass

#follow these u'll get ur ans in numericals

5 structural isomers

the isomers are:

n-exane :   ch3ch2ch2ch2ch2ch3

2-methylpentane :   ch3ch(ch3)ch2ch2ch3

3-methylpentane :   ch3ch2ch(ch3)ch2ch3

2,3-dimethylbutane :   (ch3)2chch(ch3)2

2,2-dimethylbutane :   (ch3)3cch2ch3