Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE MainChemistryAldehydes and Ketones

An alkene 'P' with molecular formula C ₅ H ₁₀ undergoes reductive ozonolysis to yield two carbonyl compounds, 'Q' and 'R'. Compound 'Q' gives a silver mirror with ammoniacal silver nitrate, while compound 'R' does not. Both 'Q' and 'R' give a yellow precipitate when treated with I ₂ and NaOH . The IUPAC name of alkene 'P' is :

Options

  1. APent-2-ene
  2. B2-Methylbut-1-ene
  3. C2-Methylbut-2-ene
  4. DPent-1-ene

Correct answer

C. 2-Methylbut-2-ene

Step-by-step solution

Compound 'Q' gives a positive Tollens' test (silver mirror), indicating it is an aldehyde. Compound 'R' gives a negative Tollens' test, indicating it is a ketone. Both 'Q' and 'R' give a positive iodoform test (yellow precipitate with I ₂ and NaOH ). The only aldehyde that gives a positive iodoform test is acetaldehyde ( CH ₃ CHO ). Thus, 'Q' is acetaldehyde (2 carbon atoms). Since the starting alkene 'P' has 5 carbon atoms ( C ₅ H ₁₀ ), the ketone 'R' must have 5 - 2 = 3 carbon atoms. The only 3-carbon ketone is a

Practice Aldehydes and Ketones on Quantrex Academy →

More from Aldehydes and Ketones

Consider the following reaction. The major product (P) formed is: 2026' x ' is the product which is obtained from benzene by reacting it with carbon monoxide and hydrogen chloride in the presence of cuprous chloride. ' y ' is the major product obtain 2026' x ' is the product which is obtained by the hydrolysis of prop-1-yne in the presence of mercuric sulphate under dilute acidic medium at 333 K. ' y ' is the product which is obtai 2026Given below are two statements: Statement-I: The condensation reaction between CH₃-CH=O and under optimum pH will produce . Statement-II: The molecule will generate Ph-CH=O in the 2026An organic compound " x " where molar ratio of C, O and H are equal, on treatment with 50 % KOH under reflux followed by acidification produced " y ". The most likely structure of 2026Given below are the four isomeric compounds ( P , Q , R , S ) Identify correct statements from below. A. Q , R and S will give precipitate with 2,4- DNP . B. P and Q will give posi 2026Given below are two statements: Statement I : Cross aldol condensation between two different aldehydes will always produce four different products. Statement II : When semicarbazid 2026Which of the following statements are TRUE about Haloform reaction?: A. Sodium hypochlorite reacts with KI to give KOI. B. KOI is a reducing agent. C. , -unsaturated methylketone ( 2026 Full Aldehydes and Ketones list All JEE Main PYQs