Question

HELP ME PLS 20 POINTS

Answer 1

1- Se 2-Na 3- I guess Si as well 4-Ar 5-O

Step-by-step explanation:

• Ionization energy increases as we go right in period
• Ionization energy increases as we go upwards in groups
• Atomic radius increases as we go downwards in groups
• Atomic radius increases as we go left in periods
• Atomic radius decreases as we go right in periods so when atoms loses electron or more the smaller its radius becomes