Home
Class 12
CHEMISTRY
An optically active compound H(C(5)H(6)O...

An optically active compound `H(C_(5)H_(6)O)` on treatment with `H_(2)` in the presence of Lindlar's catalyst gave a compound I `(C_(5)H_(8)O)`. Upon hydrogenation with `H_(2)` and Pd/C, Compound H gave J `(C_(5)H_(12)O)`. Both `I` and `J` were found to b optically inactive. Select the correct statements.

A

J gives positive halloform test

B

H gives white precipitate with `[Ag(NH_(3))_(2)]^(+)`

C

Compound H liberates one mole of `H_(2)` per mole of H when treated with Na

D

J gives positives test with Jone's reagent

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the reactions and compounds involved step by step. ### Step 1: Identify the Structure of Compound H Given the molecular formula of compound H is \( C_5H_6O \), we can calculate the degree of unsaturation (DU) to understand its structure. **Degree of Unsaturation Calculation:** \[ DU = \frac{(2 \times \text{number of C}) + 2 - \text{number of H}}{2} \] Substituting the values: \[ DU = \frac{(2 \times 5) + 2 - 6}{2} = \frac{10 + 2 - 6}{2} = \frac{6}{2} = 3 \] This indicates that compound H has 3 degrees of unsaturation, which could mean it contains either: - One triple bond and one double bond, or - One ring and one double bond. Since compound H is optically active, it must have a chiral center. ### Step 2: Propose a Structure for Compound H A possible structure for compound H that is optically active and fits the formula \( C_5H_6O \) could be: \[ \text{H} - C \equiv C - C(OH) - CH_2 - CH_3 \] This structure has a chiral center at the carbon with the hydroxyl group (OH), making it optically active. ### Step 3: Reaction with Hydrogen and Lindlar's Catalyst When compound H reacts with \( H_2 \) in the presence of Lindlar's catalyst, it undergoes partial hydrogenation, leading to compound I \( (C_5H_8O) \). The reaction can be represented as: \[ \text{H} - C \equiv C - C(OH) - CH_2 - CH_3 + H_2 \xrightarrow{\text{Lindlar's catalyst}} \text{I} \] The resulting compound I will have a double bond and will be optically inactive because it lacks a chiral center. ### Step 4: Further Hydrogenation with Pd/C Next, compound H undergoes complete hydrogenation with \( H_2 \) and Pd/C to form compound J \( (C_5H_{12}O) \). The reaction can be represented as: \[ \text{I} + H_2 \xrightarrow{\text{Pd/C}} \text{J} \] Compound J is a saturated compound and also optically inactive. ### Step 5: Analyze the Statements Now, we need to evaluate the statements provided in the question: 1. **Statement A**: J gives a positive haloform test. - **Incorrect**: Compound J does not have a methyl ketone group, so it will not give a positive haloform test. 2. **Statement B**: H gives a white precipitate with Ag(NH3)2^+ (Tollens' reagent). - **Correct**: Compound H contains a terminal alkyne, which gives a positive Tollens' test. 3. **Statement C**: Compound H liberates 1 mole of H2 per mole of H when treated with Na. - **Correct**: The acidic hydrogen in the terminal alkyne will react with sodium to release hydrogen gas. 4. **Statement D**: J gives a positive test with Jones reagent. - **Correct**: Compound J is a secondary alcohol and will give a positive test with Jones reagent. ### Final Conclusion The correct statements are B, C, and D. ---

To solve the problem, we need to analyze the reactions and compounds involved step by step. ### Step 1: Identify the Structure of Compound H Given the molecular formula of compound H is \( C_5H_6O \), we can calculate the degree of unsaturation (DU) to understand its structure. **Degree of Unsaturation Calculation:** \[ DU = \frac{(2 \times \text{number of C}) + 2 - \text{number of H}}{2} ...
Promotional Banner

Topper's Solved these Questions

ALLEN-TEST PAPERS-part-2 Chemisty
  1. One of the important compound containing P-N bonds is phosphazens. One...

    Text Solution

    |

  2. A (C(9)H(8)O(2)Br(2))undersetDeltaoverset(NaHCO(3))rarr Ph-CH =CHBr+CO...

    Text Solution

    |

  3. Both compartments in the above diagram are larege and contain ideal ga...

    Text Solution

    |

  4. Which molecular orbital of O(2) have a nodal plane which is perpendicu...

    Text Solution

    |

  5. Select INCORRECT about inert pair effect.

    Text Solution

    |

  6. An optically active compound H(C(5)H(6)O) on treatment with H(2) in th...

    Text Solution

    |

  7. Which of the following is/are independent of path?

    Text Solution

    |

  8. underset((ii)H^(+))overset("Heated with aq. NaOH for prolonged time")r...

    Text Solution

    |

  9. underset((ii)H^(+))overset("Heated with aq. NaOH for prolonged time")r...

    Text Solution

    |

  10. underset((ii)H^(+))overset("Heated with aq. NaOH for prolonged time")r...

    Text Solution

    |

  11. {:(,"Column I",,"Column 2",,"Column 3",),(,"Enthalpy and",,"Entropy ch...

    Text Solution

    |

  12. {:(,"Column I",,"Column 2",,"Column 3",),(,"Enthalpy and",,"Entropy ch...

    Text Solution

    |

  13. {:(,"Column I",,"Column 2",,"Column 3",),(,"Enthalpy and",,"Entropy ch...

    Text Solution

    |

  14. In one litre of 3M solution of NaOH, H(2)SO(4) is added until 27.4 Kca...

    Text Solution

    |

  15. The enthalpy of hydrogenation of cyclohexene is 119.5kJ mol^(-1). If r...

    Text Solution

    |

  16. Select number of species in which bond angle at nitrogen is greater th...

    Text Solution

    |

  17. X is the number of hydrogen bonds that surround each H(2)O molecule in...

    Text Solution

    |

  18. X is the maximum number of atoms that are in one plane in isobutylene....

    Text Solution

    |