A mixture of two or more liquids that distill (vaporize) at the same composition as the original mixture. For example a 95% ethanol and 5% water mixture will retain the same composition in the vapor state as in the liquid state. Since this mixture boils at a lower temperature than either of the individual components, it is difficult to remove the last 5% of water in an ethanol solution.
Sources Checked for Data in Record
- Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998