Hydrocarbons PYQs Set 5 (PDF)

Set 5 of 15 · Questions 121-150 of 435

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Mere Teacher · Previous Year Questions NEET Chemistry · Hydrocarbons · Set 5 (Q121-150)
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121. $When propyne is passed through a red hot iron tube at 873 K, the reaction gives product having molecular formula of$ (1) $C_{7} H_{8}$ (2) $C_{9} H_{12}$ (3) $C_{8} H_{10}$ (4) $C_{6} H_{6}$ 122. $The reaction of toluene with C 1_{2} in presence of F e C 1_{3} gives X and reaction in presence of light gives Y . Thus, X and Y are$ (1) $X = Benzal chloride, Y = 0 ‐chlorotoluene$ (2) $X = m ‐chlorotoluene, Y = p ‐chlorotoluene$ (3) $X = o - and p -chlorotoluene, Y = Trichloromethyl benzene$ (4) $X = Benzyl chloride, Y = m ‐chlorotoluene$ 123. $Identify the correct catalyst and reaction conditions for the controlled oxidation of methane to (i) methanol (X), (ii) methanal (Y) and ethane to (iii) ethanoic acid (Z) (X) (Y) (Z)$ (1) $Mo_{2} O_{3} /Δ (CH_{3} COO)_{2} Cu /523 K /100 atm Cu /523 K /100 atm Mn /Δ$ (2) $Cu /523 K /100 atm Mo_{2} O_{3} /Δ; (CH_{3} COO)_{2}; Mn /Δ$ (3) $(CH_{3} COO)_{2} Mn /Δ Mo_{2} O_{3} /Δ$ (4) $Mo_{2} O_{3} /Δ Cu /523 K /100 atm (CH_{3} COO)_{2} Mn /Δ$ 124. $What is the number of moles of tertiary carbon atoms in a molecule of isobutane?$ (1) $One$ (2) $Two$ (3) $Three$ (4) $Four$ 125. $Ethyl phenyl acetylene (1-phenyl-1-butyne) on reduction with partially deactiveated palladised charcoal (Lindlar's catalyst) gives$ (1) (2) (3) (4) 126. $Increasing order of electrophilic substitution for following compounds$ (1) $I V < I < I I < I I I$ (2) $I I I < I I < I < I V$ (3) $I < I V < I I I < I I$ (4) $I I < I I I < I < I V$ 127. $The number of π -bonds and lone pair(s) present in the major benzenoid product, which formed when benzene is reacted with acetyl chloride in the presence of anhydrous aluminium chloride, respectively are$ (1) $5 : 2$ (2) $4 : 2$ (3) $5 : 4$ (4) $6 : 4$ 128. $Assertion (A): Reaction of 1-butene with HBr gives 1 -bromobutane as major product. Reason (R): Addition of hydrogen halides to alkenes proceeds according to Markownikoff's rule. The correct answer is$ (1) $A and R are correct and R is the correct explanation of A$ (2) $A and R are correct but R is not the correct explanation of A$ (3) $A is correct but R is not correct$ (4) $A is not correct but R is correct$ 129. $Which one of the following nitro-compounds does not react with nitrous acid$ (1) $H_{3} C - C (= O) - C H (C H_{3}) - N O_{2}$ (2) $H_{3} C - C H_{2} - C H_{2} - N O_{2}$ (3) $H_{3} C - C H (H_{3} C) - C H_{2} - N O_{2}$ (4) $H_{3} C - C (C H_{3}) (C H_{3}) - N O_{2}$ 130. $The correct order of boiling points of following molecules is (i) n -Hexane (ii) 2-methylpentane (iii) 2,3-dimethylbutane$ (1) $i > ii > iii$ (2) $iii > ii > i$ (3) $iii > i > ii$ (4) $i > iii > ii$ 131. $The alkane that gives only one monochloro product on chlorination with C l_{2} in presence of diffused sunlight is$ (1) $2,2‐dimethylbutane$ (2) $neopentane$ (3) $n ‐pentane$ (4) $isopentane$ 132. $Identify the ortho and para directing groups towards aromatic electrophilic substitution reactions from the following list - OH - CN - CO_{2} H - OCH_{3} - NHCOCH_{3} - CHO I II III IV V VI$ (1) $I, IV, V$ (2) $II, III, VI$ (3) $I, II, IV$ (4) $IV, V, VI$ 133. $2 -hexene (i) O_{3} (ii) H_{2} O Products The two products formed in above reaction are$ (1) $Butanal and acetaldehyde$ (2) $Butanoic acid and acetaldehyde$ (3) $Butanal and acetic acid$ (4) $Butanoic acid and acetic acid$ 134. $In the following substitution reaction: product^{’} P^{’} formed is:$ (1) (2) (3) (4) 135. $3-phenylpropene on reaction with HBr gives (as a major product) :$ (1) $C6H5CH(Br)CH2 CH3$ (2) $C6H5CH2CH (Br) CH3$ (3) $C6H5CH2CH2CH2 Br$ (4) $C6H5CH(Br) CH = CH2$ 136. $Identify A in the given chemical reaction. Mo_{2} O_{3} 773 K, 10 - 20 atm A (major product)$ (1) (2) (3) (4) 137. $The major product of the following chemical reaction is + HBr (C_{6} H_{5} CO)_{2} O_{2} ?$ (1) $(H_{3} C)_{2} C H - C H_{2} - C H_{2} - B r$ (2) $(H_{3} C)_{2} C H - C H_{2} - C H_{2} - O - C O C_{6} H_{5}$ (3) (4) $(C H_{3})_{2} C H - C H (B r) - C H_{3}$ 138. $For the preparation of alkanes, aqueous solution of sodium or potassium salt of carboxylic acid is subjected to$ (1) $hydrogenation$ (2) $oxidation$ (3) $electrolysis$ (4) $hydrolysis.$ 139. $Halogenation of which one of the following will yield m-substituted product with respect to methyl group as a major product?$ (1) (2) (3) (4) 140. $In Friedel‐Crafts reaction, toluene can be prepared by$ (1) $C_{6} H_{6} + C H_{3} C 1$ (2) $C_{6} H_{5} C 1 + C H_{4}$ (3) $C_{6} H_{6} + C H_{2} C 1_{2}$ (4) $C_{6} H_{6} + C H_{3} C O C 1$ 141. $Given below are two statements: Statement (I): On nitration of m-xylene with HNO_{3}, H_{2} SO_{4} followed by oxidation, 4-nitrobenzene-1,3-dicarboxylic acid is obtained as the major product. Statement (II): - CH_{3} group is o/p-directing while - NO_{2} group is m-directing group. choose the correct answer from the options given below:$ (1) $Both Statement I and Statement II are false$ (2) $Statement I is false but Statement II is true$ (3) $Statement I is true but Statement II is false$ (4) $Both Statement I and Statement II are true$ 142. $An alkene A on reaction with O_{3} and Z n - H_{2} O gives propanone and ethanal in equimolar ratio. Addition of HCl to alkene A gives B as the major product. The structure of product B is$ (1) $H_{3} C - C H (C l) - C H (C H_{3}) - C H_{3}$ (2) $C l - C H_{2} - C H_{2} - C H (C H_{3}) - C H_{3}$ (3) $H_{3} C - C H_{2} - C H (C H_{2} C l) - C H_{3}$ (4) $H_{3} C - C H_{2} - C (C H_{3}) (C l) - C H_{3}$ 143. $In the process of formation of nitronium ion, nitric acid acts as$ (1) $a base$ (2) $an acid$ (3) $a catalyst$ (4) $a solvent$ 144. $A compound is treated with N a N H_{2} to give sodium salt. Identify the compound.$ (1) $C_{2} H_{2}$ (2) $C_{6} H_{6}$ (3) $C_{2} H_{6}$ (4) $C_{2} H_{4}$ 145. $Predict the product C obtained in the following reaction of 1‐butyne.$ (1) $C H_{3} - C H_{2} - C H_{2} - C (I) (C l) - H$ (2) $C H_{3} - C H_{2} - C H (I) - C H_{2} - C l$ (3) $C H_{3} - C H_{2} - C (I) (C l) - C H_{3}$ (4) $C H_{3} - C H (C l) - C H_{2} - C H_{2} - I$ 146. $CH_{3} CH_{2} COO^{-} Na^{+} NaOH + ? Heat CH_{3} - CH_{3} + Na_{2} CO_{3} Consider the above reaction and Identify the missing reagent/chemical.$ (1) $B_{2} H_{6}$ (2) $Red. phosphorus$ (3) $CaO$ (4) $DIBAL-H$ 147. $The compound or ion which is not aromatic in the following is$ (1) (2) (3) (4) 148. $Which one of the following conformations of cyclohexane is the least stable?$ (1) $Half-chair$ (2) $Boat$ (3) $Twisted-boat$ (4) $Chair$ 149. $In which of the following reactions, t -butyl benzene is formed 1.Benzene + t -butyl chloride \to AlCl 3 2.Benzene + (CH_{3})_{2} C = CH_{2} \to BF 3. HF 3.Benzene + t -butyl alcohol \to H 2 SO 4 4.Benzene + butanoyl chloride \to AlCl 3 Zn / HCl$ (1) $1,2 and 3$ (2) $2,3 and 4$ (3) $1,2 and 4$ (4) $1,3 and 4$ 150. $Addition of HBr to propene in presence of a peroxide takes place contrary to Markovnikov rule. This can be explained by the mechanism involving$ (1) $electrophile$ (2) $free radical$ (3) $nucleophile$ (4) $carbene$