Answer:
A liquid mixture of two or more substances that retains the same composition in the vapor state as in the liquid state when distilled or partially evaporated under a certain pressure is known as a constant boiling mixture. These are also known as azeotropes/azeotropic mixtures.
Explanation:
An example: Ethanol and water forms an azeotrope mixture boiling at 78.15oC. The composition of the mixture is (95.5% ethyl alcohol and 4.5% water)
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