Assertion: All halogens are coloured.
Reason: The halogens absorb visible light.

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

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

• If the assertion is true but the reason is false.

• If both the assertion and reason are false.

Assertion: F-F bond has low bond dissociation energy.
Reason: The fluorine has lower reactivity.

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

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

• If the assertion is true but the reason is false.

• If both the assertion and reason are false.

Assertion: Cuprous ion (Cu⁺) is colorless whereas cupric ion (Cu²⁺) is blue in the aqueous solution.
Reason: Cuprous ion (Cu⁺) has unpaired electrons while cupric ion (Cu²⁺) does not.

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

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

• If the assertion is true but the reason is false.

• If both the assertion and reason are false.

Assertion: Dinegative anion of oxygen (O^2-) is quite common but negative anion of sulphur (S^2-) is less common.
Reason: Covalency of oxygen is two.

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

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

• If the assertion is true but the reason is false.

• If both the assertion and reason are false.

Methyl orange is the example of which type of dye ?

• Acid dye

• Mordant dye

• Azo dye

• Both (a) and (c)

Enzymes with two sites are called :

• apoenzyme

• allosteric enzyme

• holoenzyme

• conjugate enzyme

Teflon is a polymer of :

• tetra fluoroethylene

• tetrabromoethylene

• tetraiodoethylene

• tetrachloroethylene

Lucas test is used for the determination of :

• alcohols

• alkyl halides

• phenols

• aldehydes

49.

Which ofthe following is involved in Sandmeyer's reaction ?

• Ferrous salt

• Diazonium salt

• Ammonium salt

• Cupromonium salt

The intermediate formed in aldol condensation is :

• aldol

• carbanion

• alcohol

• alpha-hydrogen ester