29bicarbonate (hydrogen carbonate)
HCO₃⁻
30bisulfate (hydrogen sulfate)
HSO₄⁻
31bisulfite (hydrogen sulfite)
HSO₃⁻
32biphosphate (hydrogen phosphate)
HPO₄²⁻
33dihydrogen phosphate
H₂PO₄⁻
34biphosphite (hydrogen phosphite)
HPO₃²⁻
35dihydrogen phosphate
H₂PO₃⁻