Quiz-16 Aldehydes and Ketones

Aldehydes and Ketones Quiz-16

Dear Readers,

The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry. .

Q1.  Pleasant odours of common fruits is due to:

•  Alcohol
•  Fats
•  Sugars
•  Esters

Solution
Many fruits contain esters such as pineapple has ethyl butyrate, raspberry has isobutyl methanoate, banana has n-pentyl ethanoate, orange has octyl ethanoate, etc.

Q2.The end product of the reaction

•  Alkane
•  Carboxylic acid
•  Ketone
•  Sodium slat of carboxylic acid

Solution

Cannizzaro’s reaction.

Q3.   Show the final product of the reaction

•  
  
  
  
•  
  
  
  
•  
  
  
  
•  
  
  
  

Solution

Q4. Lactic acid on oxidation with Fenton’s reagent gives main product:

•  CH₃ COOH
•  H₂ C₂ O₄
•  CH₃ COCOOH
•  None of these

Solution

Fenton’s reagent FeSO₄+H₂ O₂ as well as Tollen’s reagent give pyruvic acid.

Q5. Urea is preferred to ammonium sulphate as a nitrogenous fertilizer because

•  It is more soluble in water
•  It is cheaper than ammonium sulphate
•  It is quite stable
•  It does not cause acidity in the soil

Solution

 

Urea is one of the most important fertilizer as it does not change pH of soil. Urea, after hydrolysis gives ammonia and CO_2. Ammonia is taken up by plants leaving behind CO₂.CO₂ is a very weak acidic oxide. It doesn’t affect pH of soil.

Q6. Aldehyde are the first oxidation product of

•  Primary alcohol
•  Secondary alcohol
•  Tertiary alcohol
•  Dihydric alcohols

Solution

Q7.Which of the following compounds does not have a carboxyl group?

•  Methanoic acid
•  Ethanoic acid
•  Picric acid
•  Benzoic acid

Solution
Picric acid is 2,4,6-trinitrophenol.

Q8.Ascorbic acid is a/an:

•  Vitamin C
•  Enzyme
•  Protein
•  None of these

Solution
Ascorbic acid (C₆ H₈ O₆) is called vitamin C, found in citrus fruits.

Q9.Which of the following organic compounds answers to both iodoform test and Fehling’s test?

•  Ethanol
•  Methanal
•  Ethanal
•  Propanone

Solution

The compound which contains –COCH₃ group in its structure, give positive iodoform test and the compound which contains –CHO group give positive Fehling test. In ethanal, CH₃ CHO both the groups are present, hence it responds to both iodoform test and Fehling’s test.

Q10. Which one of the following is reduced with zinc and hydrochloric acid to give the corresponding hydrocarbon?

•  Ethyl acetate
•  Acetic acid
•  Acetamide
• Butan-2-one

Solution

Carbonyl compounds are reduced to corresponding alkanes with (Zn+ conc.HCl). It is called Clemmensen reduction.