3 Salt Tests

Question 1

1. Flame test - lilac flame
2. Nitric acid, no fizzing
3. silver nitrate- cream precipitate

What salt was tested?

Answer 1

potassium bromide

KBr

Question 2

What is the ionic equation for the silver nitrate and Cl^- ion?

Answer 2

Ag⁺ + Cl^- ⇒ AgCl

white precipitate

Question 3

NaOH was added- dirty green precipitate formed

What ion is present?

Answer 3

Fe²⁺

Question 4

What colour is Ca2+ in a flame test?

Answer 4

red/orange

Question 5

What is the chemical test for Cl-, Br- and I- ions?

Answer 5

Add nitric acid

if no fizzing, add silver nitrate

white, cream and yellow precipitate shows presence of Cl-, Br- and I- ions respectively

Question 6

1. Flame test - red flame
2. Nitric acid, no fizzing
3. silver nitrate- yellow precipitate

What salt was tested?

Answer 6

lithium iodide

Question 7

hydrochloric acid was added- no fizzing

barium chloride was added- white precipitate formed

What ion is present?

Answer 7

sulphate ion

SO₄^2-

Question 8

What is the ionic equation for the hydrochloric acid test on carbonate ion?

Answer 8

2H⁺ + CO₃^2- ⇒ H₂O + CO₂

Question 9

What is the ionic equation for the silver nitrate and Br^- ion?

Answer 9

Ag⁺ + Br^- ⇒ AgBr

cream precipitate

Question 10

1. Flame test - lilac flame
2. Nitric acid, no fizzing
3. silver nitrate- cream precipitate

What salt was tested?

Answer 10

potassium bromide

KBr

Question 11

1. Flame test - yellow flame
2. HCl added, no fizzing
3. BaCl₂ added- white precipitate

What salt was tested?

Answer 11

Na₂SO₄

sodium sulphate

Question 12

What is the ionic equation for the NaOH test on Fe²⁺ ions?

Answer 12

Fe²⁺ + 2 OH^- ⇒ Fe(OH)₂

Question 13

What colour is Li+ in a flame test?

Answer 13

red

Crimson red

Question 14

What is the chemical test for CO₃^2-ion?

Answer 14

Add hydrochloric acid

fizzing shows carbonate ion is present

Question 15

What is the ionic equation for the silver nitrate and I^- ion?

Answer 15

Ag⁺ + I^- ⇒ AgI

yellow precipitate

Question 16

1. NaOH added- dirty green precipitate
2. hydrochloric acid added- no fizzing
3. Barium chloride added- white precipitate

What salt was tested?

Answer 16

FeSO₄

iron (II) sulphate

Question 17

1. NaOH added- blue precipitate
2. hydrochloric acid added- no fizzing
3. Barium chloride added- white precipitate

What salt was tested?

Answer 17

CuSO₄

copper (II) sulphate

Question 18

What colour is K+ in a flame test

Answer 18

lilac

Question 19

What is the ionic equation for the NaOH test on NH₄⁺ ions?

Answer 19

NH₄⁺ + OH^- ⇒ NH₃ + H₂O

ammonia gas formed

damp red litmus turns blue

Question 20

What colour is Na+ in a flame test

Answer 20

yellow

Question 21

Describe how you test for the following cations

Na+, K+. Li+ and Ca2+

Answer 21

Flame test

• Dip platinum wire into dilute HCl*
• Dip wire into salt*
• run end of wire up and down edge of roaring flame*

Observe colour

Question 22

1. NaOH added- brown precipitate
2. hydrochloric acid added- fizzing

What salt was tested?

Answer 22

Fe₂(CO₃)₃

iron (III) carbonate

Question 23

What is the chemical test for SO₄^2-ion?

Answer 23

Add hydrochloric acid

If no fizzing, add barium chloride solution

white precipitate shows sulphate ion is present

Question 24

1. NaOH added- dirty green precipitate
2. hydrochloric acid added- no fizzing
3. Barium chloride added- white precipitate

What salt was tested?

Answer 24

FeSO₄

iron (II) sulphate

Question 25

1. Flame test - red/orange flame 2. Nitric acid, no fizzing 3. silver nitrate- white precipitate What salt was tested?

Answer 25

calcium chloride CaCl₂

Question 26

What is the test for NH₄⁺ ion?

Answer 26

Add **NaOH** **if no precipitate formed**, hang **damp red litmus paper** over edge of test tube NH₃ produced turns litmus paper **blue** NH₄⁺ + OH^- ⇒ NH₃ + H₂O

Question 27

NaOH was added- blue precipitate formed What ion is present?

Answer 27

Cu²⁺

Question 28

What is the ionic equation for the NaOH test on Cu²⁺ ions?

Answer 28

Cu²⁺ + OH^- ⇒ Cu(OH)_{2 Blue precipitate}

Question 29

What is the ionic equation for the NaOH test on Fe³⁺ ions?

Answer 29

Fe³⁺ + 3 OH^- ⇒ Fe(OH)3 brown precipitate

Question 30

What is the test for Fe2+, Fe3+ and Cu2+ ions?

Answer 30

- dissolve the salt you are testing in water - add **sodium hydroxide (NaOH)** - observe colour of metal hydroxide precipitate

Question 31

1. Flame test - red/orange flame 2. Nitric acid, no fizzing 3. silver nitrate- white precipitate What salt was tested?

Answer 31

calcium chloride CaCl₂

Question 32

NaOH was added- brown precipitate formed What ion is present?

Answer 32

Fe³⁺

Question 33

What is the ionic equation for the barium chloride test on sulphate ion?

Answer 33

Ba²⁺ + SO₄^2- ⇒ BaSO₄