Water

Question 0

Detailing amount of substance in a chemical

Answer 0

Quantitative analysis

Question 1

Detailing the kind of substance in a sample

Answer 1

Qualitative analysis

Question 2

Negative ion

Answer 2

Anions

Question 3

Positive ion

Answer 3

Cation

Question 4

Calcium flame colour

Answer 4

Brick red

Question 5

Sodium flame colour

Answer 5

Yellow

Question 6

Potassium flame colour

Answer 6

Lilac

Question 7

Copper flame colour

Answer 7

Green/blue

Question 8

Identifying ions with precipitation

Answer 8

Add naoh
Because many metal hydroxides are insoluble
Precipitation occurs
Precipitate formed identifies ion

Question 9

Precipitate from NaOH and aluminium

Answer 9

White

Question 10

Precipitate from NaOH and calcium

Answer 10

White

Question 11

Precipitate from NaOH and copper

Answer 11

Pale blue

Question 12

Precipitate from NaOH and iron (II)

Answer 12

Green

Question 13

Precipitate from NaOH and iron (III)

Answer 13

Brown (rust)

Question 14

Distinguishing calcium and aluminium

Answer 14

Excess NaOH
Aluminium redissolves to form Colourless solution
Calcium unchanged

Question 15

Precipitate from water testing will always be

Answer 15

Solid hydroxide of the cation

Question 16

Identifying chloride in water

Answer 16

Mix with silver nitrate acidified with dilute nitric acid

Silver halide precipitate will be white

Question 17

Identify bromide in water

Answer 17

Mix with silver nitrate acidified with dilute nitric acid

Silver halide precipitate will be cream

Question 18

Identify iodide in water

Answer 18

Mix with silver nitrate acidified with dilute nitric acid

Silver halide precipitate will be yellow

Question 19

Ionic equation

Answer 19

Ions written separately

Shows that they’re unchanged

Question 20

Detecting ammonium ions

Answer 20

Warming unknown substance with NaOH solution

If present, smelly alkali gas given off

Question 21

Detect ammonia

Answer 21

Smell

Turns damp red litmus paper blue

Question 22

Reason for sodium floride in water

Answer 22

Reduce tooth decay

Question 23

Risk of aluminium ions

Answer 23

Linked to Alzheimer’s and digestive damage

Question 24

What makes water hard

Answer 24

Calcium and magnesium ions

Question 25

Hard to wash with hard water ,why how

Answer 25

Hard to lather Calcium and magnesium ions combine with soap Make insoluble precipitate scum on surface

Question 26

Formation of lime scale

Answer 26

Calcium and magnesium decompose to form lime scale

Question 27

Temporary hardness

Answer 27

Water that can be heated to remove compounds

Question 28

Removing hardness

Answer 28

Ion exchange column Filled with heads of resin (polymer) +vly charged Ca or Mg switches with +vly charged sodium ions That are weekly attached to resin

Question 29

Cleaning on exchange column

Answer 29

Concentrated sodium chloride solution (brine) pass through | Reload