Question

write the chemical symbol for an element in period 3 and group 7a.

Explanation:

Step1: Recall Periodic Table Structure

Periods are horizontal rows, groups are vertical columns. Group 7A (halogens), Period 3 means 3rd row.

Step2: Identify Element in Period 3, Group 7A

In Period 3, Group 7A, the element is chlorine. Chemical symbol for chlorine is Cl.

Answer:

Cl