Ncert Solutions Chemistry Class 12th

This is a Short Answer Type Questions as classified in NCERT Exemplar

Butanol is a four-carbon aldehyde, with the aldehyde group on the fourth carbon. It has a functional group and a carbonyl group that interacts dipole-dipole. Because butanol possesses a polar O-H bond, it exhibits intermolecular H bonding, which is not feasible in butanal due to the lack of a polar bond. The boiling point of butanol is higher than that of butan-1-ol.

This is a Long Answer Type Questions as classified in NCERT Exemplar

Ans: Liquid 'A' reduces ammoniacal silver nitrate and 'B' is a ketone which forms white crystalline solid on treatment with hydrogen sulphite

 This is a Long Answer Type Questions as classified in NCERT Exemplar

Ans: Functional isomers

Compound I will react faster with HCN due to less steric hindrance and greater positive charge on carbon atom of carbonyl group. Two methyl groups increase electron density on carbonyl carbon in compounds II hence the rate of nucleophilic attack is less.
Mechanism of the reaction:

 

This is a Long Answer Type Questions as classified in NCERT Exemplar

Ans: The aromatic compound 'A' does not give Tollen's reagent test, it is not an aromatic aldehyde. As it responds to an iodoform test called methyl ketone.

This is a Long Answer Type Questions as classified in NCERT Exemplar

Ans:

Fehling's test is positive when compound 'B' is used. It gives an iodoform test and proves that it is an aldehyde. Because it fails Fehling's test, compound 'C' is a ketone.

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Ans: Correct option: D

[Fe (CN)₆]^3-  ion shows magnetic moment corresponding to one unpaired electron. (CN) is a ligand with a strong field that couples electrons, resulting in hybridisation. d²sp³ and it has one unpaired electron, it has the magnetic moment of one paired electron.

  μ= $\sqrt[]{n(n+2}$   = 1 (1 + 2)

   = 3 = 1.73BM 

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Ans: Correct option: B

From the Cis and Trans forms, geometrical isomerism forms compounds. All of the valences in the MX₆ ligand are the same, resulting in an identical molecule. L is a distinct ligand in MX₅L, and it can be replaced with any other valency in the structure to create an identical molecule; the molecule does not change. Because of the presence of symmetry, which is an essential prerequisite for revealing geometrical isomerism, complexes do not show geometrical isomerism.

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Ans: Correct option: A

The term "linkage isomerism" refers to two molecules that have similar ligands but differ in the donating site of the ligand. Ambidentate is made up of two different types of donor atoms.

Example [Fe (NO₂) (H₂O)₅]Cl₂. NO₂ is Ambidentate ligand as Nand O₂ are donors.

 As a result, linkage isomerism occurs in coordinations with ambidentate ligands. Reason and Assertion are both correct.

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Ans: Correct option: B

[Cr (H₂O)₆]Cl₂ and [Fe (H₂O)₆]Cl₂ 

Due to the creation of a more stable complex ion after obtaining ion, [Cr (H₂O)₆]Cl₂ and [Fe (H₂O)₆]Cl₂ are reduced in nature. Both compounds have a coordination of 6 and so form an octahedral complex. The hybridisation state of is 3 and the oxidation state of is 2+. Hybridization is 3d⁴ and 3d⁶ is 2+. Both compounds have unpaired electrons and have weak field ligands. In both compounds, removing electrons is simple.

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Ans: Correct option: A

Toxic metal ions are removed by the chelating ligands. Chelate complexes tend to be more stable. When a solution of the chelating ligand is added to a solution containing toxic metals ligands chelates the metal ions by the formation of a stable complex.

Thus, EDT A (hexadentate ligand) forms a stable metal chelate and is used to remove toxic metal ions.

Both Assertion and Reason are correct and Reason is the correct  for Assertion.

Hence, option A is correct.