51.

Which one of the following is not a buffer solution?

• 0.8M H₂S + 0.8M KHS

• 2M C₆H₅NH₂ + 2M C₆H₅NH₃^-Br^-

• 3M H₂CO₃ + 3M KHCO₃

• 0.05M KClO₄ + 0.05M HClO₄

Time required to deposit one millimole of aluminium metal by the passage of 9.65 amperes through aqueous solution of aluminium ion is

• 30 s

• 10 s

• 30,000 s

• 10,000 s

Subunits present in haemoglobin are

• 2

• 3

• 4

• 5

Propan-1-ol can be prepared from propene by

• H₂O/H₂SO₄

• Hg(OAc)₂/H₂O followed by NaBH₄

• B₂H₆ followed by H₂O₂

• CH₃CO₂H/H₂SO₄

Which one of the following is not a surfactant?

• CH₃ - (CH₂)₁₅ - (CH₃)₂N⁺ - CH₃Br^-

• CH₃ - (CH₂)₁₄ - CH₂ - NH₂

• CH₃ - (CH₂)₁₆ - CH₂OSO₂^-Na⁺

• OHC - (CH₂)₁₄ - CH₂ - COO^-Na⁺

Assertion : Glycosides are hydrolysed in acidic conditions.

Reason : Glycosides are acetals.

• If both assertion and reason are true and the reason is the correct explanation of the assertion.

• If both assertion and reason are true and the reason is not the correct explanation of the assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Benzyl bromide when kept in acetone water it produces benzyl alcohol.

Reason : The reaction follows S_N2 mechanism.

• If both assertion and reason are true and the reason is the correct explanation of the assertion.

• If both assertion and reason are true and the reason is not the correct explanation of the assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Activity of an enzyme is pH dependent.

Reason : Change in pH affects the solubility of the enzyme in water.

• If both assertion and reason are true and the reason is the correct explanation of the assertion.

• If both assertion and reason are true and the reason is not the correct explanation of the assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Hydroxyketones are not directly used in Grignard reaction.

Reason : Grignard reagents react with hydroxyl group.

• If both assertion and reason are true and the reason is the correct explanation of the assertion.

• If both assertion and reason are true and the reason is not the correct explanation of the assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion : Trans-2-butene on reaction with Br₂ gives meso-2,3-dibromobutane.

Reason : The reaction involves syn -addition of bromine.

• If both assertion and reason are true and the reason is the correct explanation of the assertion.

• If both assertion and reason are true and the reason is not the correct explanation of the assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.