Tiêu đề ORGANIC CHEMISTRY - SOME BASIC PRINCIPLES AND TECHNIQUES A-2.pdf ✅

CLASS : XIIth SUBJECT : CHEMISTRY DATE : DPP NO. : 2 1 (b) Such dehydrohalogenation follow E2 mechanism. The driving force of such reaction is the stability of alkene produced. Since, tertiary alkyl halide can give more substituted alkene, it reacts fastest followed by secondary and primary i.e., 3° > 2° > 1°. 2 (c) Central carbon atom is chiral carbon. 3 (d) Those organic compounds, which are volatile in steam are purified by steam distillation. Since, aniline is a steam volatile compound, hence it is purified by steam distillation. 4 (b) are geometrical isomers. 5 (b) C6H5O ― possess less nucleophilicity due to stabilized nature of phenoxide ion. CH3OH is weaker acid than CH3COOH and thus CH3O ― is stronger base. Acidic order : CH3COOH > H2O > CH3OH 6 (c) Vinyl chloride is least reactive for SN reaction due to resonance 9 (b) The chain propagation step involves the use of free radical and regeneration of another free radical. 10 (b) CH3NC is methaneisonitrile. 12 (a) Benzyl carbonium is more stable due to resonance and thus, benzyl chloride is more reactive. 13 (a) It is a fact. 14 (b) + CH2 CH Cl CH2 CH Cl Topic :-ORGANIC CHEMISTRY - SOME BASIC PRINCIPLES AND TECHNIQUES HOOC H C COOH H C HOOC H C COOH H and C Maleic acid Fumaric acid SOLUTION S
CnH2nO2 is general formula for open chain acid and ester. n = 3 C3H6O2 O ∥ Acid CH3CH2 ―C ― O ― H O ∥ Easter CH3 ―C ― O ― CH3 15 (a) The Cannizzaro reaction is as HCHO + HCHO KOH(conc.) CH3OH + HCOOK+ methyl alcohol acetic acid The mechanism of Cannizzaro reaction is as Step I Attack of nucleophile OH ― to the carbonyl carbon Step II The transfer of hydride ion from anion (I) to second molecule of aldehyde and finally rapid transfer of proton takes place. 17 (a) Propanal and propanone are functional isomers H C H + OH O - Fast C O H H OH (anion I) H C H + O OH C O H H Hydride transfer C O H OH (-) C OH H H H alcohol Proton exchange fast H C H + O H (-) alcohol H C OK O acid H3C H3C C O , CH3CH2CHO
18 (a) It is a fact. 19 (a) Angle strain, α = 1 2 [109°28′ ― θ] In case of cyclopropane, θ = 60° ∴ α = 1 2 (109°28′ ― 60°) = 24°44′ 20 (d) The function of AlCl3, in Friedel-Craft reaction, is to produce electrophile, which later add to benzene nucleus
ANSWER-KEY Q. 1 2 3 4 5 6 7 8 9 10 A. B C D B B C A A B B Q. 11 12 13 14 15 16 17 18 19 20 A.