Amines are classified as primary (1o), secondary (2o) and tertiary (3o)
depending upon the number of hydrogen atoms replaced by alkyl or
aryl groups in ammonia molecule If one hydrogen atom of ammonia
is replaced by R or Ar , we get RNH2 or ArNH2, a primary amine (1o) If two hydrogen atoms of ammonia or one hydrogen atom of R-NH2 are
replaced by another alkyl/aryl(R’) group,  what would you get You
get R-NHR’, secondary amine