Question

what is the period number of this atom? * p: 33 n: 42

Explanation:

Step1: Identify element by proton number

The number of protons (P = 33) determines the element. The element with 33 protons is arsenic (As).

Step2: Determine period from periodic table

Elements in the periodic table are arranged in periods (rows). Arsenic is in the 4th period.

Answer:

4