Acetaldehyde undergoes oxidation to produce acetic acid. In this reaction the oxidizing agent used is:
Correct answer: C. K2Cr2O7
- A. HI
- B. LiAlH4
- C. K2Cr2O7
- D. NaBH4
Explanation
Acidified potassium dichromate is the standard oxidising agent for converting an aldehyde to a carboxylic acid, turning from orange to green as chromium is reduced from plus 6 to plus 3. Lithium aluminium hydride and sodium borohydride are reducing agents and would drive the reaction the other way, back towards the alcohol. Hydrogen iodide is a reducing agent as well.
This question appeared on the UHS MDCAT 2025 paper, which you can sit online with every answer explained.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Reactivity of Aldehydes and Ketones
The polar carbonyl group makes aldehydes and ketones undergo nucleophilic addition, reduction and condensation reactions. Aldehydes are generally more reactive and oxidise readily to carboxylic acids, whereas ketones resist mild oxidation; reactions with hydrogen cyanide, sodium bisulfite and 2,4-DNP help identify their behaviour.
Practise Aldehydes and Ketones
679 free Aldehydes and Ketones MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Reactivity of Aldehydes and Ketones questions
Benzaldehyde gives a positive test with Tollens reagent but a negative one with Fehling's solution. This shows that
Oxidation of an aldehyde with acidified potassium permanganate gives
Which of the following compounds is a ketone?
In Aldehydes and Ketones, carbon of carbonyl group is ____________?
Fehling solution react with HCHO to form precipitate of _____________?
Silver mirror is a test for ____________?