Periodicity

Question 1

Metalloid

Answer 1

Non-Metals with a combination of metal and non-metal properties

Question 2

Reactivity of Metals going Down a Group

Answer 2

• In the S block, reactivity of metals increases
• Transition metals are generally unreactive
• Lanthanides generally aren’t encountered but form 3+ ions and have similar reactivity to one another
• Actinides are radioactive metals (only uranium and thorium naturally occur)
• Non-metals decrease in reactivity

Question 3

Atomic Radius Down a Group

Answer 3

• Increases
• Nuclear charge increases but shielding also increases so there is a weaker attraction between the outer electron and the nucleus

Question 4

Atomic Radius along a Period

Answer 4

• Decreases
• Nuclear charge increases but shielding stays the same so the outer electron is more attracted to the nucleus

Question 5

Ionisation Energy Down a Group

Answer 5

• Decreases
• Nuclear Charge increases but so does shielding so the outer shell electron becomes easier to remove

Question 6

Ionisation Energy along a Period

Answer 6

• Generally increases
• Nuclear charge increases and shielding stays the same so the outer shell electron is harder to remove
• Exceptions of groups 2-3 and groups 5-6 where it decreases

Question 7

What kind of structure do Na, Mg, and Al have?

Answer 7

• Giant metallic structures
• Lattice
• Regularly arranged ions surrounded by a sea of delocalised electrons

Question 8

What structure does Si have?

Answer 8

• Giant Covalent structure
• It’s a metalloid
• 4 covalent bonds

Question 9

What is Ar?

Answer 9

A noble gas

Question 10

Trend in MP across Period 3

Answer 10

• Increases up to silicon. then decreases after that
• Na, Mg, and Al are metallically bonded and have strong electrostatic forces of attraction
• Silicon is giant covalent and has strong covalent bonds
• After silicon the rets are simple molecular and have weak VDWs

Question 11

Trend in BP across Period 3

Answer 11

• Increase up to aluminium and the decreases
• Silicon as a liquid isn’t giant covalent

Question 12

Ionisation Energy across Period 3

Answer 12

• Increases
• Exceptions of Al and Sulfur
• Al outer electron is in a higher energy level so it’s easier to remove (further from the nucleus)
• Sulfur has a pair of electrons in its outer shell that repel each other making it less stable and easier to remove