8.1 - Group 2

Question 1

Why are group 2 elements reducing agents?

Answer 1

The outermost electrons in the second shell (s2) are readily lost to form stable 2+ ions (undergoes oxidation and is the reducing agent, reduced another species)

Question 2

what are the physical properties of group 2 alkaline earth metals? (3)

Answer 2

1. Atomic radius increases down the group
2. Reactivity increases down the group
3. Ionisation energy decreases down the group

Question 3

What do group 2 elements react with oxygen to form? give general formula

Answer 3

metal oxides, MO

Question 4

Write the reaction of magnesium and oxygen and the oxidation number changes

Answer 4

:)

Question 5

What do group 2 elements react with water to form? give general formula

Answer 5

alkaline hydroxide, M(OH)₂

Question 6

Write the reaction of strontium and water and the oxidation number changes

Answer 6

:)

Question 7

What is the trend for solubility in group 2 hydroxides?

Answer 7

Increases down the group so pH increases as more OH- ions are released

Question 8

Describe the trend in alkalinity of group 2 hydroxides down the group

Answer 8

• Solubility increases
• pH increases
• Alkalinity increases

Question 9

What are the two uses for group 2 hydroxides?

Answer 9

1. Mg(OH)2 and CaCO3 - neutralises excess HCL in the stomach, for indigestion - antacids
2. Ca(OH)2 - neutralises acidic soils

Question 10

Give the general equation for the reaction between metal oxides and water

Answer 10

metal oxide + water -> metal + hydroxide

Question 11

Write the reaction of calcium oxide and water

Answer 11

:)

Question 12

Give the general equation for the reaction between metals and dilute acids

Answer 12

Metal + acid -> salt + hydrogen

Question 13

Write the reaction of magnesium and dilute hydrochloric acid and the oxidation number changes

Answer 13

:)