Reaction of cyclohexanone with dimethylamine in the presence of catalytic amount of an acid forms a compound if water during the reaction is continuously removed. The compound formed is generally known as

Amongst the following the most basic compound is

Which one of the following methods is neither meant for the synthesis nor for separation of amines?

An organic compound having molecular mass 60 is found to contain C = 20%, H = 6.67% and N = 46.67% while rest is oxygen. On heating it gives NH₃ along with a solid residue. The solid residue give violet colour with alkaline copper sulphate solution. The compound is