What is the difference between a primary group and a secondary group? a primary group is large and impersonal; a secondary group is small and purely instrumental in function. a primary group is small, consisting of emotional face-to-face relationships; a secondary group is larger and impersonal. a primary group is large and impersonal; a secondary group is small, consisting of emotional, face-to-face relationships. a primary group is small and impersonal; a secondary group is large and consists of face-to-face relationships.