1. Sb   Calcium   Antimony   Tungsten   Mercury   Hint Half-n-half Clue   2. Co   Sulfur   Cobalt   Zinc   Xenon   Half-n-half Clue   3. Ag   Silver   Helium   Lithium   Sulfur   Half-n-half Clue   4. Mn   Calcium   Phosphorus   Manganese   Carbon   Half-n-half Clue   5. S   Sulfur   Gold   Lead   Chlorine   Half-n-half Clue   6. U   Sodium   Copper   Lead   Uranium   Half-n-half Clue   7. C   Carbon   Hydrogen   Fluorine   Copper   Half-n-half Clue