Make Copper Sulfate From Copper and Sulfuric Acid (3 Ways)

66K5526

Intro: 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

26 Comments

sir please give balance chemical equations

give the balanced reaction for electrochemistry

I would do this just to get the crystals. Are they toxic? They look cool!
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.
I am in dilemma whether i can make copper sulfate by electrochemical method by using two graphita electrodes and copper scrap resting down the bottom of the container ???
Please guide me if it is possible.
Here i dont want to use copper anode.
Very true. I just wanted to know if was safe, so make sure kids can't get to it :D

Well, it's all natural but not exactly safe.:) I say it isnatural because copper sulfate crystal is the mineral chanthcosite (spellcheck please;))

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
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.

I have seen photos of a magnesium sulfate electrolysis, it seemed quite a mess of milky light blue precipitate: I assume by color that this was mostly copper hydroxide contaminated with magnesium hydroxide and perhaps some copper sulfate. The problem with epsom salt crystals is that it is a dodecahydrate, it is cheap because it is mostly water: MgSO4.12H2O. The bottom line is it does not provide much sulfate ion on a percentage to total weght basis.

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?

The coppery red scum that turn into dark red is cuprous oxide,

You can add concentrate 20% to 35% of hydrogen peroxide to it and it will dissolve into the copper sulfate solution and you will have a clean electrode again.

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.
what can you do with this after you make this????
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.
More Comments