Periodicity

Question 1

Across a period covalent radius

Answer 1

Decreases

Electron shells stays the same
Nuclear charge increases- more strongly attracted to nucleus

Question 2

Down a group the covalent radius

Answer 2

Increases

Nuclear charge increases
More electron shells
Number of shells outweighs nuclear charge- each extra layer shields the outer electrons from the nucleus so the outer electrons are less strongly attracted to the nucleus

Question 3

Down a group the electronegativity

Answer 3

Decreases

No. of filled electron shells increases- screens the bonded electrons from the nuclear charge so electrons are less strongly attracted to the atom

Question 4

Across a period electronegativity

Answer 4

Increases

Nuclear charge increases

Question 5

Electronegativity

Answer 5

A measure of attraction for electrons in a covalent bond

Higher electronegativity= stronger attraction for electrons