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Question 1

Colour of Litmus in an acidic solution

Answer 1

Red

Question 2

Colour of Litmus in a basic solution

Answer 2

Blue

Question 3

Colour of Universal Indicator [Increasing pH]

Answer 3

Red — Purple

Question 4

pH Colour Range of Phenolphthalein

Answer 4

Colourless - Pink; Colour Change [8.3 - 10]

Question 5

pH Colour Range of Methyl Orange

Answer 5

Red - Yellow; colour change [3.1 - 4.4]

Question 6

pH Colour Range of Bromothymol Blue

Answer 6

Yellow - (Green) - Blue; colour change [6.0 - 7.6]

Question 7

Describe the detoxification process of the cycad

Answer 7

The seeds of the cycad are toxic and carcinogenic, thus:

Anaerobic Fermentation and Leaching:
Fermentation involves soaking and burning the plant to fully ripen.
Leaching involves placing the cycad seeds in dilly bags and dissolve the water-soluble toxins under running water. Still water is not used as the toxins are not fully soluble

Question 8

Describe a natural buffer system

Answer 8

Seawater has a buffer system involving carbonic acid and hydrogen carbonate.

Question 9

Describe the Indigenous treatment of acids and bases

Answer 9

Clay and ochre were dried and crushed before adding water to form a paste, applied to the skin or ingested.

Clay is a detoxifying agent that neutralises excess acid in the stomach, relieving stomach pains

Aluminium

Question 10

Chemical Makeup of Complex Ions

Answer 10

Transitional Metal + Ligand Molecule/Ion

Question 11

Common Examples of Ligands

Answer 11

Water, Ammonia, Chloride, Hydroxide

Question 12

Purpose of the Ligand in a Complex Ion

Answer 12

Ligands act as an electron donor

Question 13

Formal Term for the bond between the transitional metal and the ligand

Answer 13

Coordinate covalent bond

Question 14

Recall the general solubility rules

Answer 14

SNAAP + Group 1 metals:
Sodium
Nitrate
Ammonium
Acetate
Potassium

Exception: Lithium Phosphate

Question 15

Neutralisation in Industry

Answer 15

Sodium Carbonate is used to neutralise acid spills and acidic wastage to minimise environmental damage; weak bases are used as exothermic.

Question 16

57

Answer 16

57

Question 17

Limitations of pH indicators

Answer 17

Limitations:
- The substance must be in solution or gaseous; can only measure moisture
- Destroys sample
- Slightly acidic
- Qualitative not quantitative
- Solution must be colourless/ transparent or translucent or will distort results
- Affected by temperature

Question 18

Environmental monitoring

Answer 18

Quality of
- Air
- Soil
- Water

Heavy Metals + Trace Elements

Question 19

Flame Colour of Barium Ion

Answer 19

Pale Green

Question 20

Flame Colour of Calcium Ion

Answer 20

Orange-Red

Question 21

Flame Colour of Magnesium Ion

Answer 21

No Colour

Question 22

Precipitation Test for Barium Ion

Answer 22

Addition of sulfate ion produces a white precipitate

Question 23

Precipitation Test for Calcium Ion

Answer 23

Addition of sulfate ion produces a white precipitate

Question 24

Flame Colour of Lead Ion

Answer 24

Trick Question; Poisonous as a vapour

Question 25

Precipitation Test for Silver Ion

Answer 25

Addition of chloride ion produces a white precipitate Addition of bromide ion produces a cream precipitate Addition of an iodide ion produces a yellow precipitate

Question 26

Precipitation Test for Copper Ion

Answer 26

Addition of a strong base produces a blue precipitate

Question 27

Flame Colour of Copper Ion

Answer 27

Blue-Green

Question 28

Precipitation Test for Iron (II) Ion

Answer 28

Addition of a strong base produces a green precipitate

Question 29

Precipitation Test for Iron (III) Ion

Answer 29

Addition of a strong base produces a brown precipitate

Question 30

Sequence for testing cations

Answer 30

Chloride ions, sulfate ions, hydroxide/base

Question 31

Precipitation Test for Chloride Ion

Answer 31

Addition of silver ion produces a white precipitate; decomposes in sunlight

Question 32

Precipitation Test for Bromide Ion

Answer 32

Addition of silver ion produce a cream precipitate

Question 33

Precipitation Test for Iodide Ion

Answer 33

Addition of silver ion produces a yellow precipitate

Question 34

Precipitation Test for Hydroxide Ion

Answer 34

Addition of copper ion produces a blue precipitate Addition of iron (II) ion produces a green precipitate Addition of iron (III) ion produces a brown precipitate Litmus - Blue

Question 35

Test for Acetate Ion

Answer 35

Litmus - Red

Question 36

Test for Carbonate Ion

Answer 36

Nitric acid; bubbling [limewater test]

Question 37

Precipitation Test for Sulfate Ion

Answer 37

In acidic solution, white precipitation with barium

Question 38

Precipitation Test for Phosphate Ion

Answer 38

In basic solution, white precipitation with barium

Question 39

Sequence for testing anions

Answer 39

Nitric acid, barium, ammonium + barium, silver