T-butyl and n-butyl

Answer 1

(CH3)3C- is t-butyl group.

CH3CH2CH2CH2- is n-butyl group.

Answer 2

T-butyl refers to the tert-butyl group, which consists of three methyl groups attached to a central carbon atom. N-butyl, on the other hand, refers to the normal butyl group, which consists of a four-carbon chain with a linear structure. T-butyl is more bulky and branched compared to n-butyl, which affects its reactivity and steric hindrance in chemical reactions.