Question

Two elements X and Y have valencies of 5 and 3, and 3 and 2, respectively. The elements X and Y are most likely to be respectively (a) copper and sulphur
(b) sulphur and iron
(c) phosphorus and nitrogen
(d) nitrogen and iron

Answer 1

Answer:

Nitrogen and iron is the correct answer

Answer 2

Answer is Option (d)

Explanation:

• Based on the electronic configuration and group number the elements valency are decided.  

For ex.,

• Alkali metal - Group I has 1 valence electron

• Alkaline earth metal - Group II has 2 valence electron

• Boron group - 13 group has 3 valence electron

• Carbon group - 14 group has 4 valence electron

• Nitrogen group- 15 group has 3 and 5 valence electron

• Oxygen group - 16 group has 2 valence electron

• Halogen group- 17 group has 1 valence electron

• Inert gases - 18 group has 0 valence electron

Element X has valence electron 3 and 5. So it belongs to Nitrogen group.  

Element Y - valence electron are 3 and 2. So it belongs to d block  element.

Element X is nitrogen

Element Y is iron