1. C   Carbon   Xenon   Krypton   Zinc   Hint Half-n-half Clue   2. Sb   Magnesium   Antimony   Uranium   Bromine   Half-n-half Clue   3. Co   Calcium   Cadmium   Silver   Cobalt   Half-n-half Clue   4. N   Krypton   Osmium   Nitrogen   Hydrogen   Half-n-half Clue   5. Pt   Potassium   Copper   Platinum   Helium   Half-n-half Clue   6. H   Cobalt   Copper   Hydrogen   Sulfur   Half-n-half Clue   7. Os   Iridium   Fluorine   Osmium   Nitrogen   Half-n-half Clue