Sodium Hydroxide Cation Tests

Question 1

Cu+2

Answer 1

Blue precipitate
Copper (II) Hydroxide
Cu(OH)2

Question 2

Fe+2

Answer 2

Green precipitate
Iron (II) Hydroxide
Fe(OH)2

Question 3

Fe+3

Answer 3

Brown precipitate
Iron (III) Hydroxide
Fe(OH)3

Question 4

NH4+1

Answer 4

Ammonia gas produced (no precipitate)

Question 5

How do you carry out a Sodium Hydroxide Solution cation test?

Answer 5

Dissolve the salt in distilled water. Put 1ml of this in a test tube. Then add an equal amount of dilute sodium hydroxide solution to the solution. Observe the colour of the precipitate.

Question 6

How would you test for Cu+2, Fe+2, Fe+3 or NH4+1 cations?

Answer 6

With a Sodium Hydroxide Solution Cation test.