1. Hypoiodite   S2O3   NO2   PO3   IO   Hint Half-n-half Clue   2. Monohydrogen phosphate   HPO4   NO2   O2   BrO4   Half-n-half Clue   3. Chromate   CrO4   SCN   C2O4   H2PO4   Half-n-half Clue   4. Thiocyanate   CN   SCN   BrO4   IO   Half-n-half Clue   5. Hypochlorite   NO2   ClO4   ClO   O2   Half-n-half Clue   6. Bromite   O2   ClO   BrO   BrO2   Half-n-half Clue   7. Oxalate   HPO4   CN   Cr2O7   C2O4   Half-n-half Clue