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Copper (II) Sulphate is added to Sodium Carbonate

Copper (II) Sulphate is added to Sodium Carbonate. Blue precipitate forms. What is the name of the blue precipitate?

It was a question in my IGCSE exam today and I realised we've never learnt what forms (we only learnt that blue precipitate forms but not the name) so I just guessed it and wrote Copper (II) Carbonate but I don't know if it's true.

So what really forms?

Reply 1

Pigster

You have yourself a mark.

Then again, the actual answer is, as it often is in chemistry, more complex. Na2CO3 is alkaline, so there will be OH- ions present, so you in fact get Cu2(OH)2CO3 forming.

Reply 2

C0balt

Original post by Pigster

You have yourself a mark.

Then again, the actual answer is, as it often is in chemistry, more complex. Na2CO3 is alkaline, so there will be OH- ions present, so you in fact get Cu2(OH)2CO3 forming.

OMG YES I thought I got everything wrong in question 2 *phew* I'm so desperate to get A* in the science exam because I wish to pursue chemistry or physics in the future so..I was about to cry :frown:

Well how do you read the Cu2(OH)2CO3 thing?...nvm I searched up and it says Copper basic carbonate....never heard of it.
Uh I really hope we are not meant to know that at GCSE

Reply 3

Borek

As you found - it is basic carbonate. To make things more difficult it often doesn't have well defined composition, it is more like a family of compounds, with differing ratios of copper hydroxide and copper carbonate, plus different stages of hydration.