periodicity

Question 1

atomic radius trend across period

Answer 1

decrease because number of protons increases for the same electron shielding and so greater attraction of the shells

Question 2

first ionisation energy trend and exceptions

Answer 2

generally increases due to more protons for same electron shielding

small drop between Mg and Al as it goes from 3s to 3p subshell which is further away so easier to remove

smalld rop between P and S as sulfur’s outer electron is being paired with another in the same orbital so there is slight repulsion ebtween the two

Question 3

melting point for metallic

Answer 3

stronger across due to more valence electrons

Question 4

melting point for macromolecular

Answer 4

only Si

Question 5

melting point for simple molecular

Answer 5

more electrons is more attraction so increases across