Group 2

Question 1

Why does the melting point decrease as you go down the group?

Answer 1

The distance between the positive ions and delocalised electrons increase this electrostatic forces weakens

Question 2

What is the equation for Magnesium when burning in oxygen?

Answer 2

2Mg + O2 ——> 2MgO

Question 3

What kind of flame does Magnesium burn?

Answer 3

bright white flame

Question 4

Why does an uncleaned Mg ribbon would give false results when testing for reaction rate with Mg and acid?

Answer 4

Mg and MgO would react at different rates

Question 5

Reaction with Mg and HCl

Answer 5

Mg + 2HCl —> MgCl2 + H2

Question 6

Equation for Mg with steam

Answer 6

Mg(s) + H2O (g) —-> MgO(s) + H2(g)

Question 7

Equation for Mg with warm water

Answer 7

Mg(s) + 2H2O (g) —-> Mg(OH)2 (s) + H2(g)

Question 8

Why Titanium useful?

Answer 8

abundant, low density, corrosive resitant

Question 9

How is titanium extracted?

Answer 9

using a more reactive metal (e.g. magnesium)

Question 10

What is the first step in extracting titanium?

Answer 10

TiO2 (s) is converted to TiCl4 at 900 degrees

Question 11

What is the second step in extracting titanium?

Answer 11

TiCl4 is purified by fractional distillation in an argon atmosphere

Question 12

What is the third step in extracting titanium?

Answer 12

Ti extracted by Mg at 500 degrees

Question 13

What is the first step equation for the extraction?

Answer 13

TiO2 + 2Cl2 +2C —–> TiCl4 + 2CO

Question 14

What is the second step equation for the extraction?

Answer 14

TiCl4 +2Mg —-> Ti + 2MgCl2

Question 15

What happens to the solubility of hydroxide as you go down group 2?

Answer 15

increases (more soluble)

Question 16

What is the ionic equation for Mg(OH)2

Answer 16

Mg2+ (aq) + 2OH- (aq) —–> Mg(OH)2 (s)

Question 17

What Magnesium hydroxide used in? and what equation

Answer 17

To neutralise stomach acid
Mg(OH)2 + 2HCl —> MgCl2 + 2H2O

Question 18

Why is Mg(OH)2 safe to use

Answer 18

Mg(OH)2 is weak alkaline

Question 19

What is calcium hydroxide appear as and what is it used for?

Answer 19

white precipitate
used in agriculture to neutralise acidic soils

Question 20

Why is calcium hydroxide in water more alkaline than magnesium hydroxide?

Answer 20

It is more soluble so more hydroxide ions present in solution

Question 21

What is the equation for use of calcium hydroxide as lime water?

Answer 21

Ca(OH)2 (aq) + CO2 (g) —> CaCO3 (s) + H2O (l)

Question 22

What happens to solubility of sulfate in group 2 as you go down?

Answer 22

solubility decreases

Question 23

Barium sulfate is for? and what happens after ingested?

Answer 23

Barium meal; The barium absorbs the x rays and the gut shows shows up on the image. Barium sulfate is low solubility so not absorbed in blood.

Question 24

Equation with Barium and sulfuric acid

Answer 24

Ba + H2SO4 ——> BaSO4 + H2

Question 25

What reagent is used when testing for sulfate ions?

Answer 25

BaCl2 solution acidified with HCl

Question 26

What happens when BaCl2 is added to solution with sulfate ions

Answer 26

white precipitate formed

Question 27

Ionic equation of Ba and sulfate ions

Answer 27

Ba2+ (aq) + SO4 2- (aq) —-> BaSO4(s)

Question 28

Why is HCl used?

Answer 28

To react with carbonate impurities found in salts

Question 29

Equation for HCl and carbonate?

Answer 29

2HCl + Na2CO3 —–> 2NaCl + H2O + CO2