Group 2

Question 1

What is a common name given to group 2 metals?

Answer 1

Alkaline earth metals

Question 2

What is the most reactive metal of group 2?

Answer 2

Barium

Question 3

List 3 physical properties of group 2 metals?

Answer 3

• High melting and boiling point
• Low density metals
• Form white compounds

Question 4

Does reactivity increase or decrease down group 2? Why?

Answer 4

It increases. Electrons are lost more easily because of the larger atomic radius and more shielding which decreases the pull on electrons.

Question 5

What happens to the first ionisation energy as you go down group 2? Why?

Answer 5

It decreases because the number of filled electrons increase down the group which means an increased shielding. Increased atomic radius means weaker attraction.

Question 6

What type of reaction is the reaction between group 2 elements and oxygen?

Answer 6

Redox reaction

Question 7

What are the products when group 2 elements react with water?

Answer 7

Hydroxide and hydrogen gas

Question 8

Which group 2 elements doesn’t react with water?

Answer 8

Beryllium

Question 9

What group 2 element reacts very slowly with water?

Answer 9

Magnesium

Question 10

What is oxidised and what is reduced in a reaction between group 2 metal and water?

Answer 10

The metal is oxidised and one hydrogen atom from each water is reduced

Question 11

Write and equation for the reaction of barium and water.

Answer 11

Ba + H2O -> Ba(OH)2 + H2

Question 12

What are the products when a group 2 element reacts with a dilute acid?

Answer 12

Salt and hydrogen gas

Question 13

What is formed when group 2 oxides react with water?

Answer 13

Metal hydroxide

Question 14

Write an equation for the reaction of calcium and oxygen

Answer 14

2Ca + O2 -> 2CaO + H2

Question 15

Write an equation for the reaction of calcium and hydrochloric acid

Answer 15

Ca + 2HCL -> CaCl2 + H2

Question 16

Write an equation for the reaction between a group 2 oxide and water.

Answer 16

MgO + H2O -> Mg(OH)2

Question 17

What group 2 metal oxide is insoluble in water?

Answer 17

Beryllium oxide

Question 18

What is the trend in hydroxide solubility down group 2?

Answer 18

Increases down the group as solutions contains more OH- ions. Mg(OH)2 is slightly soluble and Ba(OH)2 creates a strong alkaline solution and is much more soluble in water

Question 19

What is Ca(OH)2 used for? Write an equation related to one of its uses.

Answer 19

Calcium hydroxide is used to neutralise acids in the soil, forming neutral water.
Ca(OH)2 + 2HCl -> H2O + CaCl2

Question 20

What is Mg(OH)2 used for?

Answer 20

Acts as an antacid for treating acid indigestion, ‘milk of magnesia’.

Question 21

What is calcium carbonate used for?

Answer 21

Present in limestone and marble and used in building construction

Question 22

In reactions what do group 2 elements act as?

Answer 22

Reducing agents

Question 23

Explain why group 2 elements are reducing agents?

Answer 23

They reduce another species

Question 24

State and explain the trend in alkalinity of the solution formed when group 2 oxides are added to water?

Answer 24

Down group 2, the solubility of the metal hydroxide increases, increasing the pH and alkalinity

Question 25

Explain why ZnCl2 is a salt

Answer 25

H+ replaced by Zn2+

Question 26

Predict the formula of the zinc salt that could be formed by adding an excess of zinc to phosphoric acid?

Answer 26

Zn3(PO4)2

Question 27

Describe and explain the trend in reactivity of the Group 2 elements with dilute HCl as the group is descended

Answer 27

- Reactivity increases down the group - Atomic radius increases down the group - Shielding increases which is outweighed by increased proton charge - Nuclear attraction decreases/ionisation energy decreases

Question 28

Suggest why ice has a higher melting point than solid ammonia

Answer 28

- Ice has stronger hydrogen bonds - O has 2 lone pairs and N has 1 - O is more electronegative

Question 29

State one benefit for public health, of the reaction between chlorine gas and water

Answer 29

Removes germs/disinfects

Question 30

What trend in the behaviour of group 2 carbonates would be observed by the student?

Answer 30

- Ease of thermal decomposition decreases down the group