2.1 Periodicity

Question 1

How are the elements in the periodic table arranged?

Answer 1

In increasing atomic number

Question 2

Define ‘periodicity’

Answer 2

A repeating pattern of properties shown across different periods

Question 3

Define ‘first ionisation energy’

Answer 3

The energy needed to remove one mole of electrons from one mole of atoms in the gaseous state

Question 4

What happens to the FIE across the period?

Answer 4

Increases with a dip between group 2 and 3 and group 5 and 6

Question 5

What happens to the atomic radius across the period?

Answer 5

Decreases

Question 6

What happens to the ionic radius across the period?

Answer 6

Positive ions are smaller than their atoms

Negative ions are larger than their atoms

Question 7

Define ‘electronegativity’

Answer 7

The power of an atom to attract the pair of electrons in a covalent bond

Question 8

Structure and bonding Na to AL

Answer 8

Structure: Giant metallic lattice
Bonding: Mettalic

Question 9

Structure and bonding Si

Answer 9

Structure: Giant covalent lattice (macromoleclar)
Bonding: Covalent

Question 10

Structure and bonding P4, S8, Cl2

Answer 10

Structure: Simple molecular
Bonding: Covalent

Question 11

Structure and bonding Ar

Answer 11

Structure: Simple atomic

Very weak van der Waals forces between atoms