Ionic Size

Question

I really don't understand what this is asking... please help.

 

1.) As you move left to right across the period, there are two elements that instead show a decrease in ionization energy. Identify these elements and explain why for each.

 

 

2.) Arrange Na+,Ca2+, Cl- in order of increasing ionic size. Explain.

 

 

3.) Arrange Si, F, C from least exothermic electron affinity to most. Explain.

Answer 1

1)

This must mean Nitrogen and Oxygen: Nitrogen has higher first ionization energy then oxygen because nitrogen has

3 unpaired electrons on p sub level, which is considered as half filled energy orbital and it has lower energy than otherwise filled same orbital which we have for Oxygen. Oxygen has 4 electrons on the same sublevel. 

2)Increasing  Ca2+, Na+ and Cl-

3) Si, C, F based on electro negativity