# Calculating electrode current density

1. Jan 12, 2014

### Zensation

This is more electrical engineering than chemistry I would think.

If the current density required is 200mA per cm^2, and the electrode is a hollow copper tube that is submersed in an electrolyte in which the inside of the tube is not touching any solution, should the current be calculated based on strictly the part of the copper that is touching the solution, or all of the copper surface area?

Should the surface area of an exposed electrode only be considered the areas that are touching and conducting in the electrolyte? Or should the areas not touching be included as well, when it comes to calculating the current based off the required current density?

2. Jan 12, 2014

### Staff: Mentor

The required current density of what? Probably the contact surface to the solution - in this case, the answer is directly in the definition.

Surfaces not touching anything (except air) are probably not relevant.

3. Jan 12, 2014

### Zensation

Thank you :).

That's what I was thinking as I was typing the post out but I wanted to make sure. That sure does simplify things a lot for me.