Answer:
addition to the external medium.
Genearlly, potassium is an intracellualr ion, therefore there is higher concentration of potasium ions with its positive charges inside than outside.In addition potassium ion has many leaking potassium channels in the cell membrane,which permit K+ to escape down the gradient to the extracellular medium.
Therefore when KCl is added to the external medium of a resting neuron, the concentration of external K+ increase than intracellular medium, preventing K+ from diffusing out to the external medium, retaining their positive charges, therefore favouring depolarization of the neuron.This decreases the RMP, leading to depolarization.
If the KCl is reduced, less k+ are available outside compare to the inner medium.Therefore electrochemical gradients is sets up for leaking of K+out of the intracellular layers, caring the positive charges along, leaving the inside more negative (together with the negative charges of the anions of the intracellular layer). This is reversal of charges.And it increases the RMP.
Explanation:
