Question

How does the valency of elements vary across the second group?

Answer 1

Valency is the measure of the combining power of an element to form compounds.

• The valency of an element depends on the number of valence electrons.
• The number of valence electrons remains the same in a group.
• For elements with valence electrons lesser than or equal to $4$; the valency $=\mathrm{number}\mathrm{of}\mathrm{valence}\mathrm{electrons}$.
• For elements with valence electrons more than 4; valency $=(8-\mathrm{number}\mathrm{of}\mathrm{valence}\mathrm{electrons})$.
• In the $2^{nd}$ group, the number of valence electrons $=2$.
• So, the valency across the second group will be $2$ for all the elements.