Testing for Aqueous cations:

Question 1

Result of adding Sodium Hydroxide to: Copper(II) Cu2+

Answer 1

Pale blue precipitate of Copper(II) hydroxide Cu(OH)2.

Question 2

Result of adding Sodium Hydroxide to: Iron(II) Fe2+

Answer 2

Dirty Green precipitate of Iron(II) hydroxide Fe(OH)2

Question 3

Result of adding Sodium Hydroxide to: Iron(III) Fe3+

Answer 3

Rusty Brown precipitate of Iron(III) hydroxide Fe(OH)3

Question 4

Result of adding Sodium Hydroxide to: Aluminium Al3+

Answer 4

White precipitate of aluminium hydroxide Al(OH)3 which dissolves in excess sodium hydroxide.

Question 5

Result of adding Sodium Hydroxide to: Magnesium Mg2+

Answer 5

White precipitate of magnesium hydroxide Mg(OH)2.

Question 6

Result of adding Sodium Hydroxide to: Calcium Ca2+

Answer 6

White precipitate of calcium hydroxide Ca(OH)2