Topic A3 - Inorganic

Question 1

What block are group 2 metals in?

Answer 1

s-block

Question 2

What is the structure of group 2?

Answer 2

giant metallic structure/ metallic bonding

Question 3

What ions do group 2 form?

Answer 3

+2

Question 4

When group 2 react with water what forms?

Answer 4

alkaline solution

Question 5

What is the general trend down group 2?

Answer 5

stronger reducing agents down the group

Question 6

What is meant be a stronger reducing agent?

Answer 6

lose electrons faster

Question 7

Why are group 2 metals stronger reducing agents down the group?

Answer 7

-decreasing sum of 1st and 2nd ionisation energies
-decreasing metallic bonding strength

Question 8

Group 2 reactions: with oxygen

Answer 8

-redox reaction
-forms ionic compound (solid - due to high MP)
e.g. Mg - bright white light, white powder

Question 9

Group 2 reactions: with chlorine

Answer 9

-redox reaction
-forms ionic compound (solid - due to high MP)

Question 10

Group 2 reactions: with HCl

Answer 10

-redox reaction
-fizzing/ effervescence (hydrogen released)
-solid (reactant) disappears

Question 11

Group 2 reactions: with water

Answer 11

-redox reaction
-Mg insoluble / Ca sparingly soluble
-Sr, Ba soluble

Question 12

Group 2 reactions: with water, what are the products?

Answer 12

Metal Hydroxide + Hydrogen

Question 13

Group 2 reactions: oxides with water/ acid

Answer 13

-acid-base reaction (water acts as acid, H+ donor)

Question 14

3 uses of group 2 compounds

Answer 14

1. agriculture (calcium hydroxide)
2. antacids (magnesium hydroxide or calcium hydrogen carbonate)
3. refractory bricks (calcium oxide)

Question 15

Use of G2 compounds: agriculture

Answer 15

Calcium Hydroxide
-neutralises acidic soils

Question 16

Use of G2 compounds: antacids

Answer 16

Magnesium Hydroxide
-treats acid reflux

Question 17

Use of G2 compounds: Refractory bricks

Answer 17

Calcium Oxide (high charges and small ions = strong ionic bonding)
-heat resistant bricks
e.g. ovens, furnaces, kilns

Question 18

Group 7: Fluorine colour (pure)

Answer 18

very-pale yellow

Question 19

Group 7: Chlorine colour (pure)

Answer 19

pale green

Question 20

Group 7: Bromine colour (pure)

Answer 20

brown

Question 21

Group 7: Iodine colour (pure)

Answer 21

dark grey

Question 22

Group 7: Chlorine colour (aq)

Answer 22

colourless

Question 23

Group 7: Bromine colour (aq)

Answer 23

yellow orange

Question 24

Group 7: Iodine colour (aq)

Answer 24

brown

Question 25

Group 7: Bromine colour (organic)

Answer 25

red

Question 26

Group 7: Iodine colour (organic)

Answer 26

purple

Question 27

Group 7: Reactivity trend

Answer 27

Fluorine is the strongest oxidising agent -smallest atomic radius -least electron shielding (gains electrons most easily)

Question 28

Group 7: What is chlorine disproportionation referring to?

Answer 28

when chlorine is both oxidised and reduced in a reaction (e.g. in water, alkali)

Question 29

Gas Tests: Hydrogen

Answer 29

-lit splint Result: squeaky pop

Question 30

Gas Tests: Oxygen

Answer 30

-glowing splint Result: relights (reaction happens at about a 5x faster rate, due to conc. of oxygen being 5x greater)

Question 31

Gas Tests: Carbon Dioxide

Answer 31

-bubble through limewater (Calcium Hydroxide) Result: turns cloudy (forms white precipitate - Calcium Carbonate)

Question 32

Gas Tests: Chlorine

Answer 32

-damp blue litmus paper Result: bleaches (turns white)

Question 33

Gas Tests: Ammonia

Answer 33

-damp red litmus paper Result: turns blue

Question 34

Ion Tests: Ammonium

Answer 34

1. add sodium hydroxide and warm 2. test gas for ammonia (damp red litmus paper turns blue)

Question 35

Ion Tests: Carbonate

Answer 35

1. add dilute nitric acid 2. bubble gas produced through limewater (test gas for CO2)

Question 36

Ion Tests: Sulfate

Answer 36

1. test for and rule out carbonate (prevents false positive) 2. add barium chloride 3. white precipitate forms

Question 37

Ion Tests: Halides

Answer 37

1. test for and rule out carbonates and sulfates (using nitric acid) 2. add silver nitrate 3. add ammonia

Question 38

Ion Tests: Halides results

Answer 38

Cl- = white ppt Br- = cream ppt I- = yellow ppt

Question 39

Ion Tests: Halides results with ammonia

Answer 39

Cl- = ppt disappears with dilute ammonia Br- = only disappears if ammonia is concentrated I- = never disappears (even in concentrated ammonia)