1. Oxalate   BrO2   ClO2   C2O4   H2PO4   Hint Half-n-half Clue   2. Bromate   O2   BrO3   HPO4   H2PO4   Half-n-half Clue   3. Chromate   CrO4   O2   IO4   ClO4   Half-n-half Clue   4. Dihydrogen Phosphate   H2PO4   CN   Cr2O7   CNO   Half-n-half Clue   5. Dichromate (Cr2O7)   Cr2O7   BrO4   C2H3O2   H2PO4   Half-n-half Clue   6. Permanganate   MnO4   CNO   CN   ClO4   Half-n-half Clue   7. Cyanate   MnO4   C2H3O2   ClO   CNO   Half-n-half Clue