Periodic table trends

Question 1

What is the trend in atomic radius

Answer 1

Increases down groups, (More shells)
Decreases across period (Stronger nuclear charge pulls electrons more tightly)

Question 2

What is the trend in ionisation enthalpy

Answer 2

Increases across the period, (as the number of protons is increasing, so there is a greater nuclear charge)
Decreases down the group, as there is more shielding, and greater atomic radius.

Question 3

What is the trend in electronegativity

Answer 3

Fluorine is the most EN
Increases along the period (increased nuclear charge)
Decreases down the group (greater atomic radius)

Question 4

What is the trend in melting point

Answer 4

first 3 groups show an increase (metallic structure, with a greater charged ion as you go along, so stronger attraction)
group 4 is giant covalent, which has very strong bonds, so it is the greatest melting point
Group 5, 6, 7, and 8 are all simple molecular, so very low melt points. (Gradually increases due to greater mass so greater van der waals forces)