1.3: Periodic Table

Question 1

What are the properties of group 1 Alkali metals?

Answer 1

• Soft metals
• Silver coloured
• Highly reactive
• Rarely found in elemental form in nature

Question 2

What are the properties of group 2 Alkaline earth metals? (3)

Answer 2

• Silver coloured
• Soft metals
• Reactivity similar to alkali metals

Question 3

What are the properties of group 8 noble gases? (3)

Answer 3

• Chemically inert
• Nonmetalic
• Atomic gases at standard conditions

Question 4

What are the properties of the group 7 halogens? (3)

Answer 4

• Highly reactive
• Non-metallic
• States change down the group

Question 5

What is a Metalloid?

Answer 5

An element with properties of both metals and non-metals

Question 6

What are the properties of Transition metals? (5)

Answer 6

• At least one oxidation state
• Partially filled d-subshell
• High density, melting and boiling points
• Form coloured compounds and complex ions
• Variable valencies and ions readily undergo oxidation or reduction

Question 7

Properties of Lanthanides (rare earth metals)

Answer 7

• Shiny and silvery-white
• Stain easily when exposed to air
• Have high melting and boiling points

Question 8

Properties of Actinides

Answer 8

• All radioactive
• Very dense metals with distinctive structures
• Numerous allotropes e.g. plutonium has at least 6 allotropes

Question 9

What are the general characteristics of groups?

Answer 9

• Similar physical and chemical properties
• Size of atom increases as you go down a group
• Metallic character increases as you go down a group
• Reactivity going down group:
- metals reactivity increases
- non-metals reactivity decreases

Question 10

What is the general rule for valency?

Answer 10

• Groups 1,2,3 and 4 : valency equals group number

• Groups 5,6,7 and 8 : valency equals 8 - group number

Question 11

What is Valency?

Answer 11

The number of chemical bonds formed by an atom

Question 12

Which elements have multiple valencies?

Answer 12

• Phosphorus (P) and Nitrogen (N): Valency 3/5
• Transition metals
• Heavier elements e.g. Lead (Pb): Valency 2/4

Question 13

How do you determine the valency of an ion?

Answer 13

It is equal to its charge

Question 14

What is an empirical formula?

Answer 14

Expresses elemental composition of a compound as a ratio

Question 15

What is molecular formula?

Answer 15

The exact number of each type of atom present in one molecule of the compound