This continues until there is no a large a small( no, a large, a small ) difference in charge across the axon membranes nodes of ranviar( axon membranes, nodes of ranviar )

Potassium Sodium( Potassium, Sodium ) ions diffuse out of the neurone down the potassium electrochemical sodium( potassium, electrochemical, sodium ) concentration gradient

This makes the inside of the axon more negative positive( negative, positive ) and the outside more positive negative( positive, negative )

Some sodium potassium( sodium, potassium ) moves into the axon down the sodium potassium( sodium, potassium ) concentration gradient but the membrane is not very permeable to sodium potassium( sodium, potassium ), unlike potassium sodium( potassium, sodium ), so this amount is small large( small, large )

The diffusion of sodium potassium( sodium, potassium ) makes no all the( no, all the ) difference to the charge across the membrane. The diffusion of potassium sodium( potassium, sodium ) out of the axon is the cause of a potential difference of -70 +40( -70, +40 )mV across the membrane. This charge is stable unstable( stable, unstable ) because the electrochemical potassium concentration( electrochemical, potassium concentration ) gradient goes from the outside to the inside of the axon whereas the potassium concentration electrochemical( potassium concentration, electrochemical ) gradient goes from the inside of the axon to the outside. Sodium cannot interfere due to the impermeability permeability dark forces of nature( impermeability, permeability, dark forces of nature ).