Metal Hydroxide Tests

Question 1

How do you test for aluminium with the sodium hydroxide test?

Answer 1

Add sodium hydroxide to the sample to form a white precipitate. If when more sodium hydroxide is added the precipitate is redissolved then aluminium is present.

Question 2

How do you test for calcium with the sodium hydroxide test?

Answer 2

Add sodium hydroxide to the sample to form a white precipitate. Now use the flame test and if a a red orange flame is produced then calcium is present.

Question 3

How do you test for magnesium with the sodium hydroxide test?

Answer 3

Add sodium hydroxide to the sample to form a white precipitate. Now test for both calcium and aluminium and if both come back negative magnesium is present.

Question 4

How do you test for copper (II) with the sodium hydroxide test?

Answer 4

Add sodium hydroxide to the sample to form a blue precipitate.

Question 5

How do you test for iron(II) with the sodium hydroxide test?

Answer 5

Add sodium hydroxide to the sample to form a green precipitate.

Question 6

How do you test for iron(III) with the sodium hydroxide test?

Answer 6

Add sodium hydroxide to the sample to form a brown precipitate.

Question 7

What is the general word and symbol equations for the sodium hydroxide tests?

Answer 7

Metal Nitrate + Sodium Hydroxide -> Sodium Nitrate + Metal Hydroxide

M(NO3) + NaOH -> Na(NO3) + M(OH)

The nitrate can be substituted for other compounds like carbonate or sulfate