H2SO4:

H2SO4 → H+ + HSO4-HSO4- → H+ + SO4^2-

CA$OH$2:

Ca$OH$2 → Ca^2+ + 2OH-

NaHCO3:

NaHCO3 → Na+ + HCO3-HCO3- → H+ + CO3^2-

MgOHCl:

MgOHCl → Mg^2+ + OH- + Cl-OH- → H+ + O^2-