CO2 has same melting and boiling point. Is is due to the
structure and non-polar nature?
Yes, the fact that CO2 is overall non-polar, yet possesses 2
significant individual dipoles in a linear molecular geometry,
results in its sublimative property (ie. only existing at solid and
gaseous states) at 1 bar or 1 atm. The liquid state is only
possible at significantly higher pressures, as illustrated in its
phase diagram.
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