isomerism-position versus chain

Question

For nitriles carbon of nitrile group is part of the carbon chain. So what is the isomerism shown by pentanenitrile and 2-methylbutanentrile? Chain isomerism or position isomerism?

Answer 1

Pentanenitrile and 2-Methylbutanenitrile should be chain isomers of each other, since the parent carbon chain itself is different for these two compounds. They shouldn't be named as position isomers.