1. Chloride   HSO3   SO3   NH4   Cl   Hint Half-n-half Clue   2. Sulfide   S   HSO3   NO3   SO3   Half-n-half Clue   3. Sulfite   HSO4   SO3   HSO3   Br   Half-n-half Clue   4. Oxide   Cl   O   S   PO4   Half-n-half Clue   5. Bisulfate or Hydrogen sulfate   HCO3   HSO4   NO3   I   Half-n-half Clue   6. Hydroxide   SO3   O   OH   CO3   Half-n-half Clue   7. Iodide   HSO3   I   S   HCO3   Half-n-half Clue