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Topic: Why doesn't ethanol react with NaOH?  (Read 56163 times)

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Offline 123456789

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Why doesn't ethanol react with NaOH?
« on: September 06, 2012, 12:02:44 AM »
Ethanol is able to react with Na (s), but not NaOH (aq)
Why is it so?
In aqueous NaOH, there are mobile Na+ and OH-, so shouldn't alcohol be able to react with Na+ to form water and salt too, as it can be considered as an acid?

Offline Guitarmaniac86

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Re: Why doesn't ethanol react with NaOH?
« Reply #1 on: September 06, 2012, 12:45:50 AM »
They do react but the problem is, the alcohol reforms.

The aqueous NaOH reacts with your alcohol to form C-O-Na+ and water. The ethoxide ion will react with... water reforming the alcohol. These are in equilibrium so effectively, the net reaction is no reaction because the ethanol reforms.

Also, the pKa of sodium hydroxide may not be high enough to deprotonate ethanol to form your ethoxide... However, I cannot find a decent pKa table to compare the pKa of ethanol with sodium hydroxide.

Offline orgopete

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Re: Why doesn't ethanol react with NaOH?
« Reply #2 on: September 06, 2012, 01:51:38 AM »
You should be able to calculate the equilibrium amount of NaOEt and H2O present if solid NaOH were added to ethanol.
Author of a multi-tiered example based workbook for learning organic chemistry mechanisms.

Offline AWK

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Offline AC Prabakar

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Re: Why doesn't ethanol react with NaOH?
« Reply #4 on: September 06, 2012, 03:51:21 AM »

Offline Babcock_Hall

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Re: Why doesn't ethanol react with NaOH?
« Reply #5 on: September 06, 2012, 10:25:07 AM »
http://faculty.swosu.edu/william.kelly/pdf/ch17.pdf
There is some very good material here, but there is also a typo.  "The O-H and S-H bonds of alcohols and thiols are able to undergo homolytic cleavage to give a proton and the conjugate base."  The author must mean heterolytic cleavage.

Offline helper

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Re: Why doesn't ethanol react with NaOH?
« Reply #6 on: November 18, 2013, 03:10:19 PM »
This material is very helpfull! Thank you!

Offline AlphaScent

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Re: Why doesn't ethanol react with NaOH?
« Reply #7 on: November 18, 2013, 03:16:47 PM »
Just printed that.

Thanks AWK!!

If you're not part of the solution, then you're part of the precipitate

Offline Altered State

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Re: Why doesn't ethanol react with NaOH?
« Reply #8 on: November 18, 2013, 03:21:03 PM »

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