PDF chapter test TRY NOW

Write a short answer to the following questions in a few sentences:
 
1. Three elements A, B and C have 3, 4 and 2 electrons respectively in their outermost shell. Give the group number to which they belong in the Modern Periodic Table. Also, give their valencies
 
Element \(A\); Valence electroons \(3\); Group number \(13\); Valency .
Element \(B\); Valence electroons \(4\); Group number \(14\); Valency .
Element \(C\); Valence electroons \(2\); Group number \(2\); Valency .
  
2. Identify and name the metals out of the following elements whose electronic configurations are given below.
(a) 2, 8, 2 (b) 2, 8. 1
(c) 2.8. 7 (d) 2. 1
  
Metals are (a). , (b). Sodium and (d). as they have \(1\) to \(3\) valence electrons. Whereas, (c). is a non-metal.