Qualitative Analysis

Question 1

Colour and State of I₂

Answer 1

Natural Colour: Grey-black Solid
In Water: Brown
In Cyclohexane: Violet

Question 2

Colour and State of Br₂

Answer 2

Natural Colour : Red brown Liquid In Water: Orange
In Cyclohexane: Orange

Question 3

Colour and State of Cl₂

Answer 3

Natural State: Pale Green Gas
In Water: Pale Green
In Cyclohexane: Pale Green

Question 4

Ionic Equation for Sulfate Ions

Answer 4

Ba² (aq) + SO₄²- (aq) 🡪 BaSO₄ (s)

Question 5

Ionic Equation for ammonium ion

Answer 5

NH₄+ (aq) + OH- (aq) 🡪 NH₃ (g) + H₂O (l)

Question 6

Ionic equation for Bromide ion

Answer 6

Ag+ (aq) + Br- (aq) 🡪AgBr (s)

Question 7

Ionic equation for Chloride Ion

Answer 7

Ag+ (aq) + Cl- (aq) 🡪AgCl (s)

Question 8

Ionic equation for Iodide ion

Answer 8

Ag+ (aq) + I- (aq) 🡪 AgI (s)

Question 9

Ionic equation for test of Carbonate Ions

Answer 9

CO₃²- (aq) + 2H+ (aq) → H₂O (l) + CO₂ (g)

Question 10

Ionic for Fluoride Ion Test

Answer 10

Ag+ (aq) + F-(aq)🡪 AgF (aq)

Question 11

Observation for Iodide I- (Halide) and for further testing.

Answer 11

(Pale) yellow precipitate of AgI formed.
For further testing AgI (yellow precipitate) is insoluble in both dilute and concentrated ammonia solution.

Question 12

Observation for Bromide Br- (Halide) and for further testing.

Answer 12

Cream precipitate of AgBr formed

For further testing AgBr (cream precipitate) is insoluble in dilute ammonia solution but dissolves in concentrated ammonia solution

Question 13

Observation for Chloride Cl- (Halide) and for further testing.

Answer 13

White precipitate of AgCl formed
In further testing AgCl (white precipitate) dissolves in dilute ammonia solution

Question 14

Observation for Fluoride (Halide Ion)

Answer 14

No precipitate (AgF is soluble in silver nitrate solution)

Question 15

Testing for Carbonate Ions and observation

Answer 15

Add dilute acid to a solution or solid of a metal carbonate.
Observation: Effervescence or bubbles

Question 16

Testing for Halide Ions and for further testing

Answer 16

Add dilute nitric acid followed by silver nitrate solution.
For further testing add concentrated ammonia.

Question 17

Testing for Sulfate Ions and observations

Answer 17

Add dilute acid first and then barium chloride or barium nitrate solution to the solution Observations: White Precipitate

Question 18

Testing for ammonium Ions and observation.

Answer 18

Add sodium hydroxide solution to the compound and warm very gently. Test any gas evolved with damp red litmus paper Observation : Damp red litmus paper turns blue