Question

what are passive ion?

Answer 1

Movement of molecules DOWN the concentration gradient. It goes from high to low concentration, in order to maintain equilibrium in the cells. Does not require cellular energy.

Answer 2

Answer:

Ion

Ion is formed by the presence of any charge on an atom. It may be positive or negative.

It is an electrically charged atom or group of atoms formed by the loss or gain of one or more electrons, as a cation (positive ion) which is created by electron loss and is attracted to the cathode in electrolysis, or as an anion (negative ion) which is created by an electron gain and is attracted to the anode.

Example  

Na+(sodium ion) , Ca2+ is an example of a positive ion, or cation. S2-, named sulfide, is an example of a negative ion, or anion.

Hope this may help you ,

#Keep smiling

^_^