99. Solving a chemistry problem

1. Write the equation for the dissociation of a given electrolyte (item 2) in an aqueous solution. Determine if this electrolyte is strong or weak. Write down the expressions for the dissociation constants for each dissociation step, evaluate their values.
2. Calculate the pH of the solution of this electrolyte at a given molar concentration of CO, mol/l, taking into account only the first stage of dissociation.
variant electrolyte С0, mol/l
4 H3PO4 0.02