Module 3 (paper 1 & 3)

Question 1

Cl₂

Answer 1

Pale green in water
Pale green in organic solvent

Question 2

Br₂

Answer 2

Orange in water
Orange in organic solvent

Question 3

I₂

Answer 3

Brown in water
Violet in organic solvent

Question 4

Cl^-

Answer 4

Silver halide is white precipitate
Soluble in dilute NH₃

Question 5

Br^-

Answer 5

Silver halide is a cream precipitate
Soluble in concentrated NH₃

Question 6

I^-

Answer 6

Silver halide is a yellow precipitate
Insoluble in concentrated NH₃

Question 7

Test for CO₃^2-

Answer 7

Add dilute HNO₃
Fizzing , CO₂

Question 8

Test for SO₄^2-

Answer 8

Add Ba(NO₃)₂
Insoluble white precipitate (BaSO₄)

Question 9

Test for NH₄⁺

Answer 9

Add NaOH(aq) then heat
NH₃(g), litmus paper turns blue