200
Certain channels in cell membranes in the body allow only certain ions into the cell- they are ion specific. Would we expect the pore for a sodium or potassium ion channel to be larger, and what charge would it be specific for?
The potassium ion is larger, as it has one more quantum level, but either way the channel would be specific for a positively charged species because electron affinity is low on the left side of the table.