If there are 36 strontium and 24 phosphate, why are there not equal numbers of cations and anions?
me understand and explain.

An ion is an atom or group of atoms in which the number of electrons is not equal to the number of protons, giving it a net positive or negative electrical charge.
Due to this, anoin which is a negatively charged and is attracted to the anode (positive electrode) in electrolysis. and is considered as a proton. however Cations are positively charged and are attracted to cation ( negative electrode). its know as a electron .

So, the net positive or negative electrical charge explains the difference in the amounts of phosphate and strontium.

An ion can never have the same amount of anions and cations.

1 is the answer to this problem