Periodicity

Question 1

What is periodicity?

Answer 1

It is the repeating pattern or chemical properties going across the periods

Question 2

What happens to the atomic radii across a period?

Answer 2

Atomic radii decreases from left to right because the increased number of protons create more positive charge attraction for electrons which are in the same shell with similar shielding

Question 3

1st Ionisation energy across a period

Answer 3

Increases due to increasing number of protons as the electrons are being added to the same shell

Question 4

Why is there a small drop between Mg and Al?

Answer 4

Mg has its outer electrons in the 3s sub shell, where as Al is starting to fill the 3p subshell. Al‘s electrons is slightly easier to remove because the 3p electrons are higher in energy level

Question 5

Why is there a small drop between phosphorus and Sulfur?

Answer 5

Sulfer‘s outer electron is being paired up with an another electron in the same 3p orbital. When the 2nd electron is added to an orbital there is a slight repulsion between the 2 negatively charged electrons which makes the second electron easier to remove