Periodicity

Question 1

Trend of atomic radius period 3

Answer 1

• decreases
• same shell/same shielding
• more protons
• stronger attraction between nucleus and outer shell electrons

Question 2

Trend of electronegativity period 3

Answer 2

• increases
• more protons
• smaller atomic radius
• so stronger attraction between nucleus and 2 electrons in covalent bond

Question 3

Trend of electronegativity down a group

Answer 3

• decreases
• more shells/ more shielding
• larger atomic radius
• weaker forces of attraction between nucleus and 2 electrons in covalent bond

Question 4

Periodicity

Answer 4

This is the trend in the properties of elements across a period

Question 5

Atomic radius down group

Answer 5

• increases
• more shells/ more shielding
• greater distance between nucleus and outer electron
• so weaker forces of attraction between nucleus and other shell electrons

Question 6

Ionisation energy across period in general

Answer 6

• increases
• more protons
• same shielding/ same shells
• atomic radius decreases
• stronger attraction between nucleus and electron in outer shell

Question 7

Ionisation energy trend down a group

Answer 7

• decreases
• more shells/ more shielding
• greater distance between nucleus and outer electron
• weaker forces of attraction between nucleus and outer shell electrons
• less energy required to remove one electron from outer shell

Question 8

Trend of ionisation energy across period group 2-3

Answer 8

• decreases
• electron in group 2 - s orbital
• electron in group 3 - p orbital
• p orbital is higher energy level so easier to lose electron

Question 9

Trend of ionisation energy across period from group 5-6

Answer 9

• decreases
• group 5 - electron lost from orbital with 1 electron
• group 6 - electron lost from orbital with 2 electrons
• electron-electron pair repulsion making it easier to lost electron from p4 than p3

Question 10

Trend of melting and boiling point across period 3

Answer 10