When an electric current is passed through an electrolytic cell, how can we recognise that electrolysis is taking place?

What is the formula that this ionic compounds could form sr2+p3-o2-

Particles vibrate in a rigid structure and do not move relative to their neighbors.

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange