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Name: Jessica
Status: Educator
Grade: 9-12
Location: MD
Country: United States
Date: November 2007

What happens if you put two liquids of the same densities into the same container if they are immiscible? Will it float, sink, or be suspended midway?

The experiment you describe is really difficult to do in "the real world". Two immiscible liquids are never really totally insoluble in one another. This will change the composition of the two phases, their density and their interfacial tension. And all of these variables will depend upon small temperature changes. So your conditions are really on the point of a needle. Depending upon the precise details, Liquid "A" could be suspended in Liquid "B" (or the reverse). That is there is one continuous phase and a discontinuous phase. There could be two discontinuous phases. Depending upon the interfacial tensions these conditions could oscillate back and forth. Under such conditions even gravity could become a significant factor, so "the experiment" should be done under zero or micro-gravity conditions. Easy question, but a difficult one to carry out in practice!!

Vince Calder

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