Question

how does the valancy of an element vary across the period?​

Answer 1

Answer:

Explanation:

Across the a period, the number increase by 1.

Therefore in group 1 is of valency  1, in two valency of 2, in three valency of 3..and so on.

#answerwithquality #BAL

Answer 2

valency is changes across the period is proposed first the valency increases 1 to 4 then decreases to 0