Group 2 - Alkaline Earth Metals

Question 1

trends in atomic radius down group 2

Answer 1

Increases down the group, as the atoms has more shells of electrons making the atom bigger

Question 2

trends in melting points down group 2

Answer 2

Decreases, as the metallic bonding weakens as the atomic size increases. the distance between the positive ions and the delocalised electrons increases. Thus the electrostatic attractive forces between the positive ion and the delocalised electrons decreases.

Question 3

Trends in ionisation energy group 2

Answer 3

Decreasing. The outer shell electron are more shielded from the attraction of the nucleus as there are more electron shells in between them.

Question 4

Reactivity down group 2

Answer 4

Increases

Question 5

Mg + water

Answer 5

Mg (s) + H2O (g) –> MgO + H2

Mg + 2H2O (l) –> Mg(OH)2 + H2

Question 6

Observations for other metals (other than Mg)

Answer 6

Fizzing ( more vigorous going down)
Metal dissolving
Solution heating up
Calcium - white ppt

Question 7

Steps in extracting titanium

Answer 7

1. TiO2 is converted to TiCl4 at 900 degrees
2. TiCl4 is purified by fraction distillation in an argon atmosphere
3. Ti is extracted by Mg in an argon atmosphere at 500 degrees

TiCl4 + 2Mg –> Ti + 2MgCl2