Hydrocarbons PYQs Set 8 (PDF)

Set 8 of 16 · Questions 211-240 of 459

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Mere Teacher · Previous Year Questions JEE Main Chemistry · Hydrocarbons · Set 8 (Q211-240)
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211. $Which of the following will be most stable diazonium salt R N_{2}^{+} X^{-} ?$ (1) $C H_{3} N_{2}^{+} X^{-}$ (2) $C_{6} H_{5} N_{2}^{+} X^{-}$ (3) $C H_{3} C H_{2} N_{2}^{+} X^{-}$ (4) $C_{6} H_{5} C H_{2} N_{2}^{+} X^{-}$ 212. $With respect to the conformers of ethane, which of the following statements is true?$ (1) $Bond angle changes but bond length remains same.$ (2) $Both bond angle and bond length change.$ (3) $Both bond angle and bond length remain same.$ (4) $Bond angle remains same but bond length changes.$ 213. $The compound which gives an oily nitrosoamine on reaction with nitrous acid at low temperature, is :$ (1) $CH3NH2$ (2) $(CH3)2CHNH2$ (3) $CH3 - NH - CH3$ (4) $(CH3)3N$ 214. $The alkane from below having two secondary hydrogens is:$ (1) $4-Ethyl-3,4-dimethyloctane$ (2) $2,2,3,3-Tetramethylpentane$ (3) $2,2,4,5-Tetramethylheptane$ (4) $2,2,4,4-Tetramethylhexane$ 215. $In a reaction, CH_{2} = CH_{2} Hypoch1orous acid M R CH_{2} OH-CH_{2} OH where, M = Molecule and R = Reagent. M and R are$ (1) $C H_{3} C H_{2} O H and H C 1$ (2) $C H_{2} = C H_{2} and heat$ (3) $C H_{3} C H_{2} C 1 and NaOH$ (4) $C H_{2} C 1 - C H_{2} O H and a q . N a H C O_{3} .$ 216. $The major product (P) formed in the below reaction is H - C \equiv C - CH_{2} - CH = CH_{2} \to Br 2 (1 mol) CCl 4, 253 K P$ (1) $H - C \equiv C - CH_{2} - CH (Br) - CH_{2} (Br)$ (2) $CH (Br)_{2} - C (Br)_{2} - CH_{2} - CH = CH_{2}$ (3) $CH_{2} (Br) - CH (Br) - CH_{2} - CH = CH_{2}$ (4) $CH_{2} = CH (Br) - CH (Br) - CH = CH$ 217. $Conversion of benzene to acetophenone can be brought by$ (1) $Wurtz reaction$ (2) $Wurtz-Fittig's reaction$ (3) $Friedel-Crafts alkylation$ (4) $Friedel-Crafts acylation.$ 218. $The reagent ' X' used for the following reaction is$ (1) $Ni$ (2) $Pd / C$ (3) $LiAlH_{4}$ (4) $Na /liquid NH_{3}$ 219. $What is the number of moles of s p^{2} hybrid carbon atoms in one mole of hexa-1,4-diyne?$ (1) $5$ (2) $3$ (3) $4$ (4) $Zero$ 220. $The number of sigma (σ) and pi (π) bonds in pent-2-en-4-yne is$ (1) $10 σ bonds and 3 π bonds$ (2) $8 σ bonds and 5 π bonds$ (3) $11 σ bonds and 2 π bonds$ (4) $13 σ bonds and no π bonds$ 221. $Which of the following reagents/ reactions will convert 'A' to 'B'? 4-methyl-1-methylenecyclohexane (A) \to 4-methylcyclohexane-1-carbaldehyde (B)$ (1) $PCC oxidation$ (2) $Ozonolysis$ (3) $B H_{3}, H_{2} O_{2} /^{-} OH followed by PCC oxidation$ (4) $HBr, hydrolysis followed by oxidation by K_{2} C r_{2} O_{7} .$ 222. $Given below are two statements: Statement (I): Neopentane forms only one monosubstituted derivative. Statement (II): Melting point of neopentane is higher than n-pentane. In the light of the above statements, choose the most appropriate answer from the options given below:$ (1) $Statement I is incorrect but Statement II is correct$ (2) $Both Statement I and Statement II are correct$ (3) $Statement I is correct but Statement II is incorrect$ (4) $Both Statement I and Statement II are incorrect$ 223. $Consider the following reaction : The product 'X' is used :$ (1) $in laboratory test for phenols$ (2) $in protein estimation as an alternative to ninhydrin$ (3) $in acid base titration as an indicator$ (4) $as food grade colourant$ 224. $Which of the following compounds produces an optically inactive compound on hydrogenation?$ (1) (2) (3) (4) 225. $C_{3} H_{4} + H_{2} O \to Hg 2 + / H + 333 K [X] ⇌ T automerisation Y X and Y are respectively$ (1) $unsaturated alcohol, aldehyde$ (2) $saturated alcohol, ketone$ (3) $unsaturated alcohol, ketone$ (4) $saturated alcohol, aldehyde$ 226. $The molecular formula of the product formed when benzene is reacted with excess of chlorine molecules under ultra-violet light is$ (1) $C_{6} Cl_{6}$ (2) $C_{6} H_{3} Cl_{3}$ (3) $C_{6} H_{2} Cl_{4}$ (4) $C_{6} H_{6} Cl_{6} .$ 227. $In the given reaction the product P is$ (1) (2) (3) (4) 228. $Which of the following reactions will yield 2, 2- dibromopropane?$ (1) $CH \equiv CH + 2HBr \to$ (2) $CH3 - CH = CH2 + HBr \to$ (3) $CH3 - C \equiv CH + 2HBr \to$ (4) $CH3CH = CHBr + 2HBr \to$ 229. $In the following reaction H_{3} C-C\equivCH Red Hot Iron Tube 873 K A number of (σ) bond present in product (A) is -$ (1) $21$ (2) $9$ (3) $24$ (4) $18$ 230. $The correct acidic order of the following is I.$ (1) $I > II > III$ (2) $III > I > II$ (3) $II > III > I$ (4) $I > III > II$ 231. $But-2-yne is reacted separately with one mole of Hydrogen as shown below: B Na liq NH_{3} CH_{3} - + H_{2} C \equiv C - CH_{3} Pd/C Δ A Identify the incorrect statements from the options given below: A. A is more soluble than B. B. The boiling point & melting point of A are higher and lower than B respectively. C. A is more polar than B because dipole moment of A is zero. D. B r_{2} adds easily to B than A.$ (1) $B and C only$ (2) $B, C and D only$ (3) $A, C and D only$ (4) $A and B only$ 232. $The restricted rotation about carbon carbon double bond in 2‐butene is due to$ (1) $overlap of one s and s p^{2} ‐hybridized orbitals$ (2) $overlap of two s p^{2} ‐hybridized orbitals$ (3) $overlap ofone p and one s p^{2} ‐ hybridized orbitals$ (4) $sideways overlap of two p‐orbitals.$ 233. $In the following reaction: Product ‘P’ will not give$ (1) $Tollens’ reagent test$ (2) $Brady’s reagent test$ (3) $Victor Meyer test$ (4) $Iodoform test$ 234. $Hydrocarbon (A) reacts with bromine by substitution to form an alkyl bromide which by Wurtz reaction is converted to gaseous hydrocarbon containing less than four carbon atoms. (A) is$ (1) $CH\equivCH$ (2) $C H_{4}$ (3) $C H_{3} - C H_{3}$ (4) $C H_{2} = C H_{2}$ 235. $The pair of electrons in the given carbanion, C H_{3} C \equiv C^{-}, is present in which of the following orbitals?$ (1) $s p^{2}$ (2) $s p$ (3) $2 p$ (4) $s p^{3}$ 236. $Which from following molecules does not contain nitrogen in it?$ (1) $Pyrrole$ (2) $Piperidine$ (3) $Pyridine$ (4) $Pyran$ 237. $Reaction of phenol with chloroform in presence of dilute sodium hydroxide finally introduces which one of the following functional group ?$ (1) $-CH2Cl$ (2) $-COOH$ (3) $-CHCl2$ (4) $-CHO$ 238. $Benzene reacts with chlorine in sunlight to give a final product$ (1) $CCl_{4}$ (2) $C_{6} H_{6} Cl_{6}$ (3) $C_{6} Cl_{6}$ (4) $C_{6} H_{5} Cl$ 239. $Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is_______$ 240. $Consider the given reaction. The total number of oxygen atoms present per molecule of the product (P) is__________$