1. O   Silicon   Iodine   Oxygen   Iridium   Hint Half-n-half Clue   2. Zn   Hydrogen   Bromine   Uranium   Zinc   Half-n-half Clue   3. Si   Silicon   Carbon   Zinc   Argon   Half-n-half Clue   4. Sb   Bromine   Antimony   Hydrogen   Iron   Half-n-half Clue   5. Ir   Helium   Iridium   Zinc   Silicon   Half-n-half Clue   6. Ag   Tin   Helium   Silver   Chromium   Half-n-half Clue   7. Pb   Lead   Xenon   Iodine   Cadmium   Half-n-half Clue