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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: jjc on February 07, 2008, 02:55:01 AM

Title: How to differentiate ethanoic acid from propanoic acid
Post by: jjc on February 07, 2008, 02:55:01 AM
Hi can anyone suggest a chemical reaction to differentiate ethanoic acid from propanoic acid? it can take place through a couple of reactions? but it must be visible outcomes

THANKS
Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: Kryolith on February 07, 2008, 04:32:26 AM
Welcome to the forum  :)

Have a look at

http://en.wikipedia.org/wiki/Iodoform_reaction
Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: AWK on February 07, 2008, 06:30:54 AM
Quote from: Kryolith on February 07, 2008, 04:32:26 AM
Welcome to the forum  :)

Have a look at

http://en.wikipedia.org/wiki/Iodoform_reaction
Haloform reaction undergo ketones, not acids
Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: Kryolith on February 08, 2008, 01:06:25 PM
Quote from: AWK on February 07, 2008, 06:30:54 AM
Haloform reaction undergo ketones, not acids

I know.

Quote from: Wikipedia
Only methyl ketones, or alcohols [or acetaldehyde] with the feature:

    CH3CH(OH)-R

may undergo this reaction.

Quote from: jjc on February 07, 2008, 02:55:01 AM
Hi can anyone suggest a chemical reaction to differentiate ethanoic acid from propanoic acid? it can take place through a couple of reactions? but it must be visible outcomes

Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: ARGOS++ on February 08, 2008, 07:17:18 PM

Dear jjc;

Why not using the simple Ferrichloride-Test (FeCl3) for that?
(Would you like to have a Translation from German, if you can’t find it? )

Good Luck!
                    ARGOS++

Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: AWK on February 11, 2008, 01:59:05 AM
Quote
Why not using the simple Ferrichloride-Test (FeCl3) for that?
FeCl3 test is devoted for detection of alkanoic acids?
Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: ARGOS++ on February 11, 2008, 08:55:50 AM

Dear Mr AWK;

Of course!,  ─   That’s very true!

But at the same time the “correct” Ferrichloride-Test empowers you to distinguish between Ethanoic Acid  and Pro-pionic Acid, or more correct between Acetic Acid and “Pionic Acids”.

Apropos:   
In case of nearly pure Samples there is a much easer Test: “Put two Test Tubes” for 2 - 3 hours into the normal Fridge and watch the result.

Good Luck!
                    ARGOS++

Title: Re: How to differentiate ethanoic acid from propanoic acid
Post by: jjc on February 16, 2008, 01:38:00 AM
Quote from: Kryolith on February 08, 2008, 01:06:25 PM
Quote from: AWK on February 07, 2008, 06:30:54 AM
Haloform reaction undergo ketones, not acids

I know.

Quote from: Wikipedia
Only methyl ketones, or alcohols [or acetaldehyde] with the feature:

    CH3CH(OH)-R

may undergo this reaction.

Quote from: jjc on February 07, 2008, 02:55:01 AM
Hi can anyone suggest a chemical reaction to differentiate ethanoic acid from propanoic acid? it can take place through a couple of reactions? but it must be visible outcomes



THANKS KROYLITH! i get it already... first you reduce the carboxylic acid and then do the iodoform test... why didn't i think of it! u're a genius thanks much :)