51.

Cupric compounds are more stable than their cuprous counterparts in solid state. This is because

• the endothermic character of the 2nd IP of Cu is not so high

• size of Cu²⁺ is less than Cu⁺

• Cu²⁺ has stable electronic configuration as compared to Cu⁺

• the lattice energy released for cupric compounds is much higher than Cu⁺

The correct statement regarding the following compounds is

• all three compounds are chiral

• only I and II are chiral

• I and III are diastereomers

• only I and III are chiral

In the following reaction, the product E is

The intermediate J in the following Wittig reaction is

Among the following compounds, the one(s) that gives (give) effervescence with aqueous NaHCO₃ solution is (are)

$\underset{\mathrm{I}}{({\mathrm{CH}}_3\mathrm{CO}{)}_{2 }} \underset{\mathrm{II}}{{\mathrm{CH}}_3\mathrm{COOH}} \underset{\mathrm{III}}{\mathrm{PhOH}} \underset{\mathrm{IV}}{{\mathrm{CH}}_3\mathrm{COCHO}}$

• I and II

• I and III

• Only II

• I and IV

An amine C₃H₉N reacts with benzene sulphonyl chloride to form a white precipitate which is insoluble in aq. NaOH. The amine is

The number of amino acids and number of peptide bonds in a linear tetrapeptide (made of different amino acids) are respectively

• 4 and 4

• 5 and 5

• 5 and 4

• 4 and 3

In DNA, the consecutive deoxynucleotides are connected via

• phosphodiester linkage

• phosphomonoester linkage

• phosphotriester linkage

• amide linkage

The reaction of aniline with chloroform under alkaline conditions leads to the formation of 

• phenylcyanide

• phenylisonitrile

• phenylcyanate

• phenylisocyanate

When phenol is treated with D₂SO₄ /D₂O, some of the hydrogens get exchanged. The final product in this exchange reaction is