[Golden_4_Life]

If possible, please help to clarify this enigma for us:
We are trying to identify products of ethanol oxidation.
Procedure: Add 5.0 g of ethanol and 1 gram of 1N HydrChlor Acid to a e-flask and mix; let sit for 5 days; QS volume to 100 mL of distilled water, mix, then inject into the gas chrom.
Theoretically, the primary alcohol ETOH should be oxidized (at least partially) into ethanal and/or ethanolic acid no?

When we inspect the chromatography, we see only an ethanol peak; we were expecting to see smaller peaks for the oxidation products but saw no other peaks.

How do we know that oxidation has occured?  I checked the pH of the solution it was 1.75; the pH of control untreated sol'n was 6.95 (5 gethanol + 1 g water + QS to 100mL with water).

Evidentiary of a chemical change was that the solution pH nose dived to 1.75 vs. Control sample was 6.95---but why was this not accompanied by the appearance of signature chromatographic peaks for the oxidation products?

Our GC column and method are soundly able to detect and quantify Ethanol; moreover, the aldehydes and carboxylic acid products are polar and should be retained to some degree on the 100%wax column---but we see nothing--also the EtOH concentration was decreased by 20% relative to the Controls.  What the frigg is going on?

[Biopolmonkey]

Ethanol and hydrochloric acid alone will yield chloroethane and water. Add an oxidising agent like potassium permanganate to get aldehyde/acid products. Adjust whether the alcohol or oxidiser is in excess depending which product you would prefer.

Your pH readings don't mean a lot, as you have HCl in the reaction solution but not in the control.

[Golden_4_Life]

OK, BipolarsMonkey:  So, you're suggesting that the expected oxidation products are not there. Chloroethane would not be retained on the column.  This means if they are not there, then that would explain why we do not see them on the chrom.  You say that if add K2MnO4 then the products will appear? What molartiy, volume or such is indicated? Thank you BpM

[Biopolmonkey]

Yes, though you can use other oxidising agents also. If you put oxidation of ethanol into Google (or similar), you will find some protocols - Helpfully, this reaction appears to be used in teaching labs. Although I wrote that altering which reactant is in XS influences your major product, it looks like in practice placing the reaction mixture under reflux facillitates further oxidation from aldehyde to acid.

[Golden_4_Life]

Simple question though:  Would mixing 10 mL of ethanol with 1 mL of 1 N HCl cause a reaction to occur at room temperature?  Would this provide sufficient reactant and conditions to promote the reaction:

H3C-H2C-OH  + HCl ----> H3C-H2C-Cl + H2O.
ethanol          acid           chloro-ethane   water.

Would this rxn occur at room temp and proceed to products such that the ethanol conc would measurably decrease?

[discodermolide]

If possible, please help to clarify this enigma for us:
We are trying to identify products of ethanol oxidation.
Procedure: Add 5.0 g of ethanol and 1 gram of 1N HydrChlor Acid to a e-flask and mix; let sit for 5 days; QS volume to 100 mL of distilled water, mix, then inject into the gas chrom.
Theoretically, the primary alcohol ETOH should be oxidized (at least partially) into ethanal and/or ethanolic acid no?

When we inspect the chromatography, we see only an ethanol peak; we were expecting to see smaller peaks for the oxidation products but saw no other peaks.

How do we know that oxidation has occured?  I checked the pH of the solution it was 1.75; the pH of control untreated sol'n was 6.95 (5 gethanol + 1 g water + QS to 100mL with water).

Evidentiary of a chemical change was that the solution pH nose dived to 1.75 vs. Control sample was 6.95---but why was this not accompanied by the appearance of signature chromatographic peaks for the oxidation products?

Our GC column and method are soundly able to detect and quantify Ethanol; moreover, the aldehydes and carboxylic acid products are polar and should be retained to some degree on the 100%wax column---but we see nothing--also the EtOH concentration was decreased by 20% relative to the Controls.  What the frigg is going on?

I'm not surprised, you do not get oxidation under these conditions. What is your oxidant? What will happen is the you will get some ethyl chloride formed which will react with the ethanol to give traces of diethyl ether.

[orgopete]

No reaction is about right. 1N HCl isn't anhydrous enough to drive the reaction forward to anything. You can do a Fischer esterification with HCl gas and anhydrous ethanol without getting an appreciable amount of substitution (any?).