Cation tests

Question 1

What happens when you add water to Aluminium?

Answer 1

A white precipitate is formed

and dissolves in excess sodium hydroxide solution

Question 2

What happens when you add water to Calcium?

Answer 2

A white precipitate is formed

and remains, even when excess sodium hydroxide solution is added

Question 3

What happens when you add water to Chromium(III)?

Answer 3

A green precipitate is formed

and dissolves in excess sodium hydroxide solution

Question 4

What happens when you add water to Copper(II)?

Answer 4

A light blue precipitate is formed

and insoluble in excess sodium hydroxide solution

Question 5

What happens when you add water to Iron(II)?

Answer 5

A green precipitate is formed
and insoluble in excess sodium hydroxide solution
but after a few minutes changes to a red-brown colour.

Question 6

What happens when you add water to Iron(III)?

Answer 6

A red-brown precipitate is formed

and insoluble in excess sodium hydroxide solution

Question 7

What happens when you add water to Zinc?

Answer 7

A white precipitate is formed

and dissolves in excess sodium hydroxide solution