Testing With Sodium Hydroxide

Question 1

Chemicals that we can test for using sodium hydroxide, and their ionic formulas

Answer 1

Copper (II) ions Cu^2+

Iron (II) ions Fe^2+

Iron (III) ions Fe^3+

Aluminium Al^3+

Calcium Ca^2+

Magnesium Mg^2+

Question 2

Positive result after testing with sodium hydroxide:

Copper (II)

Answer 2

Blue precipitate

Question 3

Positive result after testing with sodium hydroxide:

Iron (II) ions

Answer 3

Green precipitate

Question 4

Positive result after testing with sodium hydroxide:

Iron (III) ions

Answer 4

Brown precipitate

Question 5

Positive result after testing with sodium hydroxide:

Aluminium

Answer 5

White precipitate

Precipitate dissolves with excess sodium hydroxide

Question 6

Positive result after testing with sodium hydroxide:

Calcium

Answer 6

White precipitate

Question 7

Positive result after testing with sodium hydroxide:

Magnesium

Answer 7

White precipitate