Testing for the type of alcohol

AI Thread Summary
To determine whether a mixture contains ethanol or isopropyl alcohol, various methods can be employed. One suggested approach is the "salting out" experiment, where salt is added to the mixture to observe if separation occurs. This method may indicate the type of alcohol present, as isopropyl alcohol is more likely to separate from water than ethanol. Additionally, using density tables for different concentrations of ethanol and isopropyl alcohol can provide a mathematical basis for identification, although careful measurement is crucial due to the small differences in density. Smelling the mixture is also mentioned as a quick, albeit less scientific, method to differentiate between the two alcohols. Engaging in both the salting out experiment and density calculations is recommended for a comprehensive understanding.
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How to test if the alcohol I have (70% alcohol and 30% purified water) is ethanol or isopropyl
How can I test if the mixture I have contains ethanol or isopropyl? Will a simple "salting out expuriment" work (adding salt and seeing whether the mixture separated or not)? Or is there a better way to check?
 
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Ethanol and isopropyl alcohol mixtures with water should be common enough to find a density table for different concentrations online (make sure if it's w/w, v/v, or v/w) and simply doing the math.
 
Mayhem said:
Ethanol and isopropyl alcohol mixtures with water should be common enough to find a density table for different concentrations online (make sure if it's w/w, v/v, or v/w) and simply doing the math.
That's... So simple I'm ashamed I haven't thought of it myself... In any way, Thank you!
 
The difference in density isn't very large so you would need to measure carefully.

Wouldn't it be easier to smell it?
 
JT Smith said:
The difference in density isn't very large so you would need to measure carefully.

Wouldn't it be easier to smell it?
Well then I should rephrase the question: I want to try the salting out method of purifing isopropyl as a fun first expuriment. Is this also good to check if the alcohol is isopropyl (if it seperates) or ethanol (if it doesn't)?
 
If one salts out and the other doesn't then the answer would be yes, wouldn't it? Or are you asking whether or not ethanol can be salted out with sodium chloride?

Since the whole point seems to be experimentation why not do both experiments? Add table salt to an isopropanol/water solution and to an ethanol/water solution and see what happens.
 
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