I have a norwegian science book for high school, and many of the assertions are confusing me. Here's one:
"In clean water the voltage between Zn and Cu is 1,1 V. Zn is negative pole. This tells us that
Zn has bigger ability than Cu to give ions to the water, and we're getting more electrons on the Zn-rod than the Cu-rod."
To get this voltage, i guess Zn has to get oxidized to Zn2+ and Cu2+ has to be reduced. But there are no Cu-ions in water, so how do they get 1,1V? Is this just rubbish?