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Flashcards in C4f Deck (7)
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1
Q

What is thermal decomposition?

A

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

2
Q

What happens when you heat a transition metal carbonate?

A
  • break down into metal oxide and carbon dioxide

- this usually results in a colour change

3
Q

What are precipitations?

A

-when a solid forms in a solution

4
Q

What is a precipitation reaction?

A

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

5
Q

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

A
  • you get insoluble hydroxide

- which the precipitates out

6
Q

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

A
  • 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
Q

Name some transition metal hydroxides and their colours.

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