1. B   Lead   Beryllium   Boron   Helium   Hint Half-n-half Clue   2. O   Oxygen   Hydrogen   Bromine   Calcium   Half-n-half Clue   3. Mn   Sulfur   Potassium   Manganese   Zinc   Half-n-half Clue   4. Xe   Iridium   Mercury   Nitrogen   Xenon   Half-n-half Clue   5. Br   Lithium   Bromine   Iron   Silver   Half-n-half Clue   6. Hg   Iridium   Krypton   Calcium   Mercury   Half-n-half Clue   7. Sn   Iron   Magnesium   Tin   Uranium   Half-n-half Clue