"The high Na⁺ concentration outside will cause some of the Na⁺ to move into the cell.

If there are no anion channels or if the anions are the slowly moving chloride ions than a separation of charge will develop opposite to that seen with the K⁺ channels.

The outside of the cell will be at a lower potential (negative) and the inside will be at a higher potential (positive).

At equilibrium the concentration force is equal and opposite to the electrical force and there is no net movement of Na⁺.

The difference in electrical potential across the cell membrane is called the Na⁺ equilibrium potential (+64) and can be determined by using the Nernst equation."

courtesy of Robert H. Parsons, Ph.D., Rensselaer Polytechnic Institute, used with permission