Question

The elements of groups,1, 2, 13, 14, 15, 16 and 17 are collectively called-

• A. Noble gases
• B. Representative or normal elements
• C. Transition elements
• D. Inner transition elements

Answer 1

The correct option is B

Representative or normal elements

In modern table elements are classified into representative elements, transition elements, inner transition, inner gases based on electronic configuration. The group number(as per old classification A group elements) of the elements represents the number of valence electrons they are called as representative elements

Group - 1 (1A)-1 valence e 15 (VA) - 5 valence e-

2 (IIA) - 2 " 16 (VIA) - 6 valance e-

3 (IIIA) - 3 " 17 (VIIA) - 7 valence e-

4 (IVA) - 4 "