|MadSci Network: Chemistry|
Yes it melts and boils but you have to get it pretty hot in a vacuum. The melting point (in vacuum) is 801C at which point you will start seeing a NaCl vapor pressure. The boiling point is 1465 in vacuum. If you tried this in air, you would get reactions with the oxygen and water in the air. Remember that when we talk about ionic, we are really talking about two different areas. NaCl has ionic bonds in the solid, true, but its ionic behavior we discuss at length is based on its properties in water solution. What happens with pure sodium chloride in a vacuum is another area of chemistry where the term ionic has different meanings.
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