I know we eschew "lists" on main, but this is a popular search topic and many good questions and answers address the question, "For characteristic X what is the most extreme chemical?" E.g.,
- Strongest acid
- Strongest organic acid
- Most dangerous: Is there any substance that's a 4-4-4 on the NFPA diamond?
- Densest gas
- Densest element
- Highest melting point
- Greatest range between melting and boiling temperature
- Strongest reducing agent
- Lowest solubility product constant
The only other good list a quick search turned up was this thread at Sciencemadness.
Can we maintain a list of these here as community wiki? Alternatively, should we create a most-extreme for these questions?