Assertion: Like bromination of benzene, bromination of phenol is also carried out in the presence of Lewis acid.
Reason: Lewis acid polarises the bromine molecule.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Reason: Lewis acid polarises the bromine molecule.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
(d) Assertion is false but reason is true.
Assertion: o-Nitrophenol is less soluble in water than the m- and p-isomers.
Reason: m- and p- Nitrophenols exist as associated molecules.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion: Bond angle in ethers is slightly less than the tetrahedral angle.
Reason: There is a repulsion between the two bulky (-R) groups.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion: Ethanol is a weaker acid than phenol.
Reason: Sodium ethoxide may be prepared by the reaction of ethanol with aqueous NaOH.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion: Phenol forms 2,4,6–tribromophenol on treatment with \(Br_2\) in carbon disulphide at 273K.
Reason: Bromine and carbon disulphide both are nonpolar.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion: p-nitrophenol is more acidic than phenol.
Reason: Nitro group helps in the stabilisation of the phenoxide ion by dispersal of negative charge due to resonance.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion: Boiling points of alcohols are greater than ethers of same molar mass.
Reason: Ethers can form intermolecular hydrogen-bonding with each other.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion: Phenols give o- and p-nitrophenol on nitration with conc. \(HNO_3\) and \(H_2\)\(SO_4\) mixture.
Reason: —OH group in phenol is o–, p– directing.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Read the passage given below and answer the following questions:
The polarity of carbon-halogen bond of alkyl halides is responsible for their Nucleophilic substitution, elimination and their reaction with metal atoms to form organ metallic compounds. Nucleophilic substitution reactions are categorized into SN1 and SN2 on the basis of their kinetic properties. Chirality has a profound role in understanding the reaction mechanisms of SN1 and SN2 reactions. SN2 reactions of chiral alkyl halides are characterized by the inversion of configuration while SN1 reactions are characterized by racemisation.
ASSERTION -REASON TYPE
A statement of assertion is followed by a statement of reason. Mark the correct choice from the options given below:
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
(i) Assertion : SN2 reactions do not proceed with retention of configuration.
Reason : SN2 reactions proceed in a single step.
(ii) Assertion : Tertiary alkyl halides show high reactivity in SN1 reaction.
Reason : Tertiary carbocation has more stability.
(iii) Assertion : Nucleophilic substitution reaction in an optically active alkyl halide gives a mixture of enantiomers.
Reason : Reaction occurs by SN1 mechanism.
(iv) Assertion : Primary allylic halides show higher reactivity in SN1 reactions than other primary alkyl halides.
Reason : Intermediate carbocation is stabilized by resonance.
Assertion: The bond between adenine and thymine is stronger than the bond between Cytocine and guanine.
Reason: Cytosine and guanine have a triple hydrogen bond while adenine and thymine have a double hydrogen bond
A. Assertion and reason both are correct statements and reason is correct explanation for assertion.
B. Assertion and reason both are correct statements but reason is not correct explanation for assertion.
C. Assertion is correct statement but reason is wrong statement.
D. Assertion is wrong statement but reason is correct statement.
Assertion :-Water has high melting point.
Reason :- Water molecules are associated with hydrogen bonding.
a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
b) Assertion and reason both are correct statements but reason is not correct explanation for assertion.
c) Assertion is correct statement but reason is wrong statement.
d) Assertion is wrong statement but reason is correct statement.
Assertion: Phenols give o- and p-nitrophenol on nitration with conc. \(HNO_3\) and \(H_2\)\(SO_4\) mixture.
Reason: —OH group in phenol is o–, p– directing.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.
Assertion : -The bond between F-F is weaker than between Cl-Cl.
Reason:- Atomic size of F is smaller than that of Cl.
a) Assertion and reason both are correct statements and reason is correct explanation for assertion.
b) Assertion and reason both are correct statements but reason is not correct explanation for assertion.
c) Assertion is correct statement but reason is wrong statement.
d) Assertion is wrong statement but reason is correct statement.
Assertion: Molarity of the solution changes with temperature.
Reason: Molarity is a colligative property.
A. If both Assertion and Reason are correct and reason is the correct explanation of Assertion .
B. If both Assertion and Reason are correct and reason is not correct explanation of Assertion
C. If Assertion is correct but Reason is incorrect.
D. If Assertion is incorrect and Reason is correct.
Assertion: o-Nitrophenol is less soluble in water than the m- and p-isomers.
Reason: m- and p- Nitrophenols exist as associated molecules.
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.
(b) Both assertion and reason are true but the reason is not the correct explanation of assertion.
(c) Assertion is true but reason is false.
(d) Assertion is false but reason is true.