Question

Q.1. An element X (2,8,2) combines separately with NO3 and (SO4)2 -, (PO4)3 - radicals.

Write the formulae of the three compounds so formed. To which group of the periodic

table does the element ‘X’ belong? Will it form covalent or ionic compound? Why?

Q.2. Two elements X and Y have atomic numbers 12 and 16 respectively. Write the

electronic configuration for these elements. To which period of the modern periodic

table do these two elements belong? What type of bond will be formed between

them and why?

Answer 1

a) On adding the number of electron of X, it is 12 which indicate Magnesium. It combine with NO₃¯ and SO₄²¯to form Mg(NO₃)₂ and Mg(SO₄). Magnesium belongs to 2^nd group which forms ionic compound due to its metallic character.

b) ₁₂X = 2 8 2 ; ₁₆Y = 2 8 6

X = Magnesium = 2^nd group and 3 period

Y = Sulphur = 6^th-A group and 3 period

The bond formed will be ionic in nature because magnesium is metallic and sulphur is non-metallic.