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Flashcards in C4f Deck (7):
1

What is thermal decomposition?

-when a substance breaks down into at least two other substances when heated

2

What happens when you heat a transition metal carbonate?

-break down into metal oxide and carbon dioxide
-this usually results in a colour change

3

What are precipitations?

-when a solid forms in a solution

4

What is a precipitation reaction?

-where two solution react and an insoluble solid form in the solution

5

What happens if you react soluble transition metal compounds with sodium hydroxide?

-you get insoluble hydroxide
-which the precipitates out

6

How can you use precipitations to test for transition metal ions?

-some insoluble transition metal hydroxides have different colours
-you can use this fact to test which transition metal ions a solution contains
-e.g. adding sodium hydroxide to an unknown soluble salt may result in an orange/brown precipitation, you know you have got iron(III) hydroxide and so have Fe3+ ions in he solution

7

Name some transition metal hydroxides and their colours.

-copper(II) hydroxide=blue solid
-iron(II) hydroxide=green/grey solid
-iron(III) hydroxide=orange/brown solid