1. O   Aluminum   Cobalt   Oxygen   Carbon   Hint Half-n-half Clue   2. Ne   Hydrogen   Iridium   Neon   Osmium   Half-n-half Clue   3. Mn   Oxygen   Manganese   Carbon   Barium   Half-n-half Clue   4. Ag   Chromium   Lithium   Silver   Chlorine   Half-n-half Clue   5. W   Beryllium   Mercury   Chlorine   Tungsten   Half-n-half Clue   6. Co   Neon   Cobalt   Argon   Chromium   Half-n-half Clue   7. Pb   Lead   Calcium   Mercury   Nickel   Half-n-half Clue