Answer is: standard metal cations are sodium cation (Na⁺), potassium cation (K⁺), magnesium cation (Mg²⁺) and calcium cation (Ca²⁺).
Soap is a salt of a fatty acid. When soap have sodium and potassim cations, that is toilet soap and when soap have magnesium and calcium cations, that soap is called metallic soap.
