Is a flow of ionized water an electric current?

Question

If $H_2O$ ions have a net electric charge and electric current is the flow of electric charge, can a stream of water ions be considered an electric current? If so, is it conceivably possible (not necessarily feasible) to use a flow of water ions in place of a copper wire carrying an electrical current in an electrical circuit? For example, in a bizarre Rube Goldberg contraption sort of situation.

Edit: I guess this question applies to any sort of ion in either gas or liquid state. I don't know enough chemistry to know if $H_2O$ ions are even a thing that exist in the real world

Answer 1

Yes, electric current is movement of any kind of charges.

The problem with your particular example is that most liquids containing ions are also conductive. Electrons will hop between molecules and equalize the ionic charges, then end up providing most of the conduction themselves.

There are cases where actual ion migration results in much of the current, such as in a battery. This process is also used in reverse in electro-plating applications.

Answer 2

Ions can indeed carry current (ex. electrolysis). "An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in a plasma.[1]"

Answer 3

Well, technically yes (assuming you mean ionized and not just "charged"). Current (in simple terms) is only the time rate of charge flow, which is not exclusively limited to electrons or any specific charge carrier. Electrolytic conductivity is well documented, naturally being higher for strong electrolytes as compared to the ones that dissociate weakly in the solvent. It certainly does happen biologically too, in ion channels. However, more massive species are less mobile in general, so when one has a choice, it is better to go with lighter species (like electrons) doing the honours!