The liquid boils at 82°C. It is clear and colorless so it is suggested that it is just water. Do you think it might be?

1 Answer
Jun 10, 2017

If the atmospheric pressure is #1*atm# then it is not WATER.........

Explanation:

When we quote a boiling point, we quote the conditions of pressure and temperature when the vapour pressure of a liquid is equal to the ambient pressure, and bubbles of vapour form directly in the liquid. The #"normal boiling point"# is specified when the ambient pressure is #1*atm#.

The normal boiling point is a characteristic property of a liquid. That of water is #100# #""^@C#; that of ethanol is #78.3# #""^@C#; that of methanol is #64.7# #""^@C#. And so your unknown liquid is none of these beasties.........

The boiling point of #"isopropyl alcohol"# is, however, #82.6# #""^@C#, so we're likely on a winner here given that it is another clear, colourless liquid. Note, however, that other confirmatory tests are to be performed before we sticks our necks out..............

In an organic lab, the confirmatory tests would be to make a few derivatives of the presumed #"isopropanol"#, check their melting points with the extensive literature, and then make the declaration.