With every electron stationed in its own orbital or paired off with each other in the higher energy level, the energy level is balanced and stable. The atoms that utilize this exception are Molybdenum, Chromium, Gold, Silver, and Copper.
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Methane, CH4, would have the lowest boiling point among the three since it has the lowest number of carbon and has no functional groups. Methanol would have the highest boiling point since it has a functional group which contains hydrogen bonding which much stronger than the one in CH3Cl. Hope this helps.<span />
