What valencies will be shown by the elements A, B, C, D and E having atomic numbers 2, 4, 8, 10, and 13 respectively.
When atomic no. is 2 then the valency shown by A – 0
When atomic no. is 4 then the valency shown by B - 2
When atomic no. is 8 then the valency shown by C - 2
When atomic no. is 10 then the valency shown by D - 0
When atomic no. is 13 then the valency shown by E - 3