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Name: john j patten
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 


Question:
Why doesn't oil and water mix? What effect does adding detergent do to a mixture of oil and water? Why does detergent change the oil and water?



Replies:
Since explanations are limited to 25 lines and no pictures (or at least only very simple ones) I would suggest looking up soap in an encyclopedia. You might also want to look at surfactant. To get you started, however, one observation in chemistry is that molecules dissolve in other molecules that have similar characteristics. (In particular, the ability or inability to distribute electronic charge is an important characteristic for solubility.) Water is a polar molecule -- that is, electronic charges are localized on specific atoms. Oil is a non-polar molecule -- electronic charges are de-localized over all atoms. Water dissolves other polar molecules and oil dissolves other non-polar molecules but water does not dissolve oil (and vice-versa). Soap molecules are large. At one end they behave like polar molecules (electronic charges are isolated) and at the other end they behave like non-polar molecules (electronic charges are de-localized). Now, what happens when you put soap in an oil/water mix?



gregory r bradburn


To add to Gregs you might try researching emulsions and emulsifiers and find out about everyday products that are mixtures of oil and water. Good luck!



michael b lomonaco



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