Question
What valencies will be shown by the elements A, B, C, D and E having atomic numbers 2, 4, 8, 10, and 13 respectively.

Answer

Valency shown by A(atomic no. 2) – 0
Valency shown by B(atomic no. 4) – 2
Valency shown by C(atomic no. 8) – 2
Valency shown by D(atomic no. 10) – 0
Valency shown by E(atomic no. 13) – 3

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