🚀 go-pugleaf

Hallo.

I have got very good answers to all the questions except the last 
one, I guess that it is related to the way I formulated the question, 
so I now intend to describe this stage a bit deeper. 

> Last the FeSO4 was removed and instead 10 ml of water was added and
> the beaker was left for 1 week to dry. My last question is why the
> water was added and the copper was not allowed to dry as it was
> after the FeSO4 was removed.

When the Fe(s) had been added to the solution it was allowed to cool 
of for about ten minutes. After that the liquid was decanted into a 
250 ml beaker, by gently pouring it down the stirring rod. 
Now there were only small lumps of copper, about one millimetre in 
diameter, left on the bottom and a very small amount if liquid. 
Then 10 ml of water was added, while stirring constantly, and the 
copper was distributed evenly over the bottom of the beaker.

After that it was left for 7 days and when we came back the copper 
was partly covered with rust and there was a white coating around the 
beaker, about as high as the water stood when we left it.

This indicates that the experiment was not completely successful, 
but why was the water added and what was the white coating left 
around the beaker?

Thanks again.

//Regards, Johan.