1. Pb   Carbon   Iodine   Nickel   Lead   Hint Half-n-half Clue   2. Kr   Krypton   Cobalt   Barium   Magnesium   Half-n-half Clue   3. P   Phosphorus   Cadmium   Carbon   Lead   Half-n-half Clue   4. Os   Potassium   Osmium   Iridium   Phosphorus   Half-n-half Clue   5. Ni   Platinum   Nickel   Argon   Tungsten   Half-n-half Clue   6. F   Lead   Osmium   Phosphorus   Fluorine   Half-n-half Clue   7. Zn   Carbon   Zinc   Chromium   Silicon   Half-n-half Clue