31.

The secondary structure of a protein refers to 

• α-helical backbone 

•  hydrophobic interactions

• sequence of α-amino acids

• sequence of α-amino acids

Which of the following reactions will yield 2, 2-dibromopropane?

• CH₃ – C ≡ CH + 2HBr →

• CH₃CH = CHBr + HBr →

• CH ≡ CH + 2HBr →

• CH ≡ CH + 2HBr →

In the chemical reaction, CH₃CH₂NH₂ + CHCl₃ + 3KOH → (A) + (B) + 3H₂O, the compounds (A) and (B) are respectively

• C₂H₅CN and 3KCl 

• CH₃CH₂CONH₂ and 3KCl

• C₂H₅NC and K₂CO₃

• C₂H₅NC and K₂CO₃

The reaction of toluene with Cl₂ in presence of FeCl₃ gives predominantly

• benzoyl chloride

• benzyl chloride

• o-and p-chlorotoluene

• o-and p-chlorotoluene

Presence of a nitro group in a benzene ring -

• activates the ring towards electrophilic substitution

• renders the ring basic

• deactivates the ring towards nucleophilic substitution

• deactivates the ring towards nucleophilic substitution

Which of the following is the correct order of decreasing S_N2 reactivity? 

• RCH₂X > R₃CX > R₂CHX

• RCH₂X > R₂CHX > R₃CX

• R₃CX > R₂CHX >RCH₂X

• R₃CX > R₂CHX >RCH₂X

In the following sequence of reactions, 

 compound ‘D’ is

• butanal

• n-butyl alcohol

• n-propyl alcohol

• n-propyl alcohol

Which one of the following is the strongest base in aqueous solution?

• Trimethylamine

• Aniline

• Dimethylamine

• Dimethylamine

The compound formed as a result of oxidation of ethylbenzene by KMnO₄ is

• benzophenone

• acetophenone

• benzoic acid

• benzoic acid

The IUPAC name of 

• 1, 1-diethyl-2-dimethylpentane

• 4, 4-dimethyl-5, 5-diethylpentane

• 5, 5-diethyl-4, 4-dimethylpentane

• 5, 5-diethyl-4, 4-dimethylpentane