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Q & A: emulsion of water in motor oil

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Most recent answer: 09/20/2020
Q:
Could someone please verify for me that type IV deionized water made from distilled water will mix with motor oil and not separate? I observed this when I was young man. We used deionized water to rinse cars off. One day my boss put the hose of deionized water into a 5 gallon bucket half full of motor oil. the mixture immediately turned chocolate milky colored and remained that way for days.
- EDWARD AYLWARD (age 47)
Las Vegas
A:

The lack of ions in the water would play a small role. I suspect that milky suspension was stable because of some detergent (molecules with hydrophilic and hydrophobic parts) in the oil. A layer of those mollecules on the surface of a water droplet can stabilize it. 

But you could try the experiment yourself. Only a small amount of oil would be needed, so as not to waste it and make more polution.

Mike W.


(published on 09/20/2020)

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