Periodic Trends

Question 1

What are 5 characteristics of elements in Group 1 (the alkali metals)?

Answer 1

• melting point decreases as you go down group
• densities increase down the group (except for potassium)
• reactivity increases down the group
• reacts with water to form hydrogen + (the alkaline metal) hydroxide
• relatively soft

Question 2

What are 6 characteristics of elements in Group 7 (the halogens)?

Answer 2

• diatomic
• non-metal
• densities increase down the group
• melting points increase down the group
• elements further up displace elements further down
• colour becomes darker as you go down the group

Question 3

What are 3 characteristics of elements in Group 8 (the noble gases)?

Answer 3

• unreactive/inert
• monoatomic gases
• do not form compounds

This is because they have a full outer shell.

Question 4

What are 7 features of transition metals?

Answer 4

• high melting points (except for mercury)
• high densities
• form colourful compounds
• variable oxidation states
• usually lose electrons
• usually unreactive
• used as catalysts many times

Question 5

What uses do noble gases bring us due to their inert natures?

Answer 5

We use argon in lamps since it does not react with the filament.
We use krypton for laser eye surgeries.
We use neon to light up signs.
We use helium to fill balloons (it is lighter than air)