TBR orgo book 2 section 5 question 40

[unDRdog]

heres the question; An alcohol, when oxidized, forms a compound that turns blue litmus papaer red. In terms of substitution, the alcohol is best described as a:
A- primary alcohol
B-secondary alcohol
C-tertiary alcohol
D-primary alcohol or secondary alcohol

Answer is A... I thought is was D but i dont understand the explination either because wont the formation of an aldehyde and a ketone both release a H ?????
Thanks everyone

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[RedSoxSuck]

heres the question; An alcohol, when oxidized, forms a compound that turns blue litmus papaer red. In terms of substitution, the alcohol is best described as a:
A- primary alcohol
B-secondary alcohol
C-tertiary alcohol
D-primary alcohol or secondary alcohol

Answer is A... I thought is was D but i dont understand the explination either because wont the formation of an aldehyde and a ketone both release a H ?????
Thanks everyone

I picked D too. LOL.
It is asking you to come with an answer which takes into account the RED litmus paper. Which is acidic. If the question stem said nothing about the litmus paper being turned from blue to red then then answer would be D. But in this case we have to choose an acidic compound as an answer. D cannot be correct since Secondary alcohols are oxidized to Ketones which is NOT acidic. Primary alcohols are oxidized to Carboxylic acid which is acidic.

Not sure if that makes sense though!

 

[unDRdog]

I picked D too. LOL.
It is asking you to come with an answer which takes into account the RED litmus paper. Which is acidic. If the question stem said nothing about the litmus paper being turned from blue to red then then answer would be D. But in this case we have to choose an acidic compound as an answer. D cannot be correct since Secondary alcohols are oxidized to Ketones which is NOT acidic. Primary alcohols are oxidized to Carboxylic acid which is acidic.

Not sure if that makes sense though!

That makes sense...THANK YOU.... i fell into the trap of thinking that the protonated hydrogens that float around in the sln are the things making it turn red...but your right...the question stem says the COMPOUND turns it red...thanks man

 

[RedSoxSuck]

np