1. Bromide   Br   HCO3   CO3   HSO3   Hint Half-n-half Clue   2. Phosphate   NO3   HSO4   PO4   OH   Half-n-half Clue   3. Iodide   HSO4   Cl   S   I   Half-n-half Clue   4. Bisulfite or Hydrogen sulfite   HSO3   HCO3   NH4   S   Half-n-half Clue   5. Bicarbonate or Hydrogen carbonate   HCO3   PO4   S   OH   Half-n-half Clue   6. Nitrate   HSO4   NO3   S   Br   Half-n-half Clue   7. Sulfite   SO3   OH   S   PO4   Half-n-half Clue