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Make Copper Sulfate from Copper and Sulfuric acid (3 ways)

video Make Copper Sulfate from Copper and Sulfuric acid (3 ways)
We make copper sulfate from copper and sulfuric acid using two chemical methods and one electrochemical method.

Copper does not directly react with sulfuric acid so some form of oxidant is needed. Hydrogen peroxide and nitric acid are excellent oxidants and the first two methods demonstrate this. The nitric acid method however produces toxic nitrogen dioxide gas so you'll need to perform this one outside or in a fumehood.

Because both chemical methods are rather expensive. A very cheap electrochemical method can be performed by running a current through two copper electrodes immersed in sulfuric acid. The copper is converted to copper ions at the positive electrode and hydrogen gas is formed at the negative electrode.

However if the electrodes are placed side by side then the copper ions will diffuse to the negative electrode and get converted back into copper. This is wasteful as you've used power to accomplish nothing. So the better way is to separate both by gravity with the positive electrode at the bottom. The denser solution of copper sulfate will remain near the bottom and thus increase efficiency.

As a side note, the electrochemical method is actually very expensive if you use batteries as your power source. The charge on a battery generates a comparatively small quantity of total copper sulfate compared to the same cost of chemicals for the chemical methods. The cheapest way is to use a DC power supply. The cost of municipal electricity is very small compared to the cost of batteries and chemicals.

Please check out our channel at http://www.youtube.com/NurdRage
cactusbush6 months ago
In the third method - using two copper electrodes; what is the coppery scum or fluff that eventually builds up heavily on the cathode? It is easy to rub off and sinks in the solution. When the reaction slows or seems to stop - is the electrolyte (copper sulfate+water+sulfuric acid) saturated with ions? Can it take no more?
Urbizzo1 year ago
well thanks
I just needed some copper sulphate to kill some mold in my well. (I am not going to drink this water)
Now the battery charger is on 6 volts (slow) and producing copper sulphate.
I am quite shure I've got mold in that water, and I will try to treat it with this copper sulphate.
If there is some other methods to kill molds in water I am also interested.
i made some of this and decided to let it evaporate and its been sitting in a bottle for months and almost nothing has happened...
So almost 18 months later, is it still in a bottle unchanged? 'Cause I've had mine in a flask for almost a week now and there's been no noticeable change either: blue liquid, pieces of copper and some blue crystals.
there's a more efficient electrochemical reaction. it involves using a magnesium sulfate solution with a copper anode:

Cu + MgSO4 + 2 H2O → H2 + CuSO4 + Mg(OH)2
that is to say, copper and a magnesium sulfate (more commonly known as epsom salt) solution is electrochemically converted into hydrogen, copper sulfate, and magnesium hydroxide... :D
NurdRage (author)  TheMadScientist2 years ago
That's not more efficient at all.

You're creating magnesium hydroxide waste!

The method using sulfuric acid doesn't produce waste.

At best you have an alternative way, but certainly not a "more efficient" way.
dioblo23454 years ago
what can you do with this after you make this????
If you have a several tons of copper(ii) sulfate, and several thousand liters of hot water, and  a small construction crew, you can turn an old apartment into a magical blue crystal cavern, as explained here:

http://www.artangel.org.uk/projects/2008/seizure

Artist on site: Roger Hiorns on Seizure from Artangel on Vimeo.



What do you mean, "What is it good for?"
;-)

NurdRage (author)  dioblo23454 years ago
If you need to ask, you probably wouldn't be interested. We're going to explore basic concepts in battery science and electroplating.
i asked this becuase i bought a chem set with wierd toxic stuff in it and one of the things in it copper sulfate ps do you know what magnisium sulfate is if so can you tell me thing that i could use it for..........
Magnesium sulfate is epsom salt.
electroplate stuff
joypad3 years ago
about how long would it take to get crystals the size of say a half brick? also how much solution would you need?
(removed by author or community request)
atx*
Prfesser4 years ago
An even cheaper way to get copper sulfate is to look for root killer preparations at the local farm supply store. Some are pure copper sulfate.
NurdRage (author)  Prfesser4 years ago
I think you missed the part where i said "for those interested in the chemistry"
My apologies. I did not watch the video, I only read the discussion you wrote.
Kaiven4 years ago
I would do this just to get the crystals. Are they toxic? They look cool!
NurdRage (author)  Kaiven4 years ago
toxic only if you eat them, or if you don't wash your hands after handling them. But as a chemist you should never touch any chemical with your bare hands.
Kaiven NurdRage4 years ago
Very true. I just wanted to know if was safe, so make sure kids can't get to it :D
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