Identification Of Anions

Question 1

Unknown substance + HCl –> effervescence

Answer 1

Feed bubbles into life water, if goes cloudy then carbonate ions present

Question 2

Why is HCl added to unknown substance

Answer 2

To remove false positives in the sulfate ion test

Question 3

Unknown substance and HCl equals no reaction

Answer 3

Add barium chloride, if white precipitate then sulfate ions

Add barium chloride, no white precipitate then no carbonate or sulfate ions present

Question 4

Unknown and nitric acid and silver nitrate equals precipitate

Answer 4

Contains halide ions

Question 5

White precipitate that dissolves in dilute ammonia forms from nitric acid and silver nitrate

Answer 5

Chloride Ions

Question 6

Cream precipitate that dissolves in concentrated ammonia formed from nitric acid and silver nitrate

Answer 6

Bromide ions

Question 7

Yellow precipitate that is insoluble in ammonia formed from nitric acid and silver nitrate

Answer 7

Iodide ions

Question 8

Why is nitric acid added to a unknown + nitric acid + silver nitrate reaction

Answer 8

Remove ions that could give false positives

Question 9

Unknown and nitric acid and silver nitrate equals no reaction

Answer 9

No halide ions present

Question 10

Dip red litmus paper in unknown and it turns blue

Answer 10

Hydroxide ions

Question 11

Dip red litmus paper in unknown and no reaction occurs

Answer 11

No hydroxide ions