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NCCS

Chemistry 2nd

Year

Ch-08 & 10 Marks.50 Timing: 1:30 hour

Q.1. Choose the correct answer. 1x20=20

I. Formula of chloroform is.(a) CH3Cl (b) CCl4 (c) CH2Cl2 (d) CHCl3

II. Baeyers reagent is.(a) 1% alkane KMnO4 (b) 1% alkaline KMnO4 (c) 1% dil.KMnO4 (d) KMnO4

III. Ammonical solution of silver nitrate reacts with(b) 2-pentyne (b) ethene (c) 2-butyne (d) ethyne

IV. Ozonolysis of 2- butene give us(a) formaldhyde (b) ozonide (c) acectaldehyde (d) molozonide

V. Addition of HCN to ethyne in the presence of suitable catalyst gives(a) acrylonitrile (b) acetylide (c) neoprene (d) glyxol

VI. Lindlers catalyst is.(a) Pb(BaSO4)/quinoline (b) Pb(BaSO4)/quinoline (c) Pd(BaSO4)/quinoline(d) Pb (BaSO3)/quinoline

VII. Unsaturated nature of alkenes can be detected by.(a) Decolorization of red Br2 water in CCl4 (b) ozonolysis(c) Decolorization of pink colour of KMnO4solution (d) all

VIII. Oxyacetylene torch is used for(a) Resins synthesis (b) ripening of fruits (c) rubber sythesis(d) For welding and cutting metals

IX. Ethyl bromide reacts with Zn and HCl to form(a) Ethane (b) Ethene (c) Ehtyne (d) propyne

X.

The presence of a double bond in a compound is the sign of(a) saturation (b) unsaturation (c) substitution (d) None

XI. The geometry of carbonium ion formed in SN1mechanism is(b) Tetrahedral (b) square planar (c) hexagonal (d) triangular planar

XII. Secondary alkyl halides show(b) SN1mecanism (b) SN2mecanism (c) both SN1 &SN2 (d) addition reaction

XIII. Which one bond has maximum bond energy?(b) CF (b) CCl (c) CBr (d) CI

XIV. The carbocation is formed in(b) SN1reaction (b) SN2reaction (c) elimination reaction (d) addition reaction

XV. Aectic acid can be obtained from CH3MgI by treatment with(b) H2O (b) CH3CHO (c) CO2 (d) HCHO

XVI. In - elimination reaction nucleophile attacks on(a) - hydrogen (b) hydrogen (c)- hydrogen (d) All of them

XVII. 1- bromobutane on reaction with alcoholic KOH gives(b) 1- butanol (b) 1- butene (c) 2- butene (d) 1- butyne

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XVIII. Which of the following is not nucleophile(b) H2O (b) H2S (c) BF3 (d) NH3

XIX. Grignard reagent is reactive due to(a) The presence of halogen atom (b) The presence of Mg atom

( c) The polarity of CMg bond (d) Electrophilic carbon

XX. Which one of the following is not associated with SN2mechanism(a) 100% inversion of confrguration (b) 2ndorder reavtion

( c) Tertiary alkyl halide (d) change of hybridization from sp3to sp

2in transtion state

Q.2. Give short answer of the followings 10x2=20

i. How can you convert 1-Butene into 1-butyene?ii.

Identify each letter product.Propene Br2 A KOH B HCN C

alcohol

iii. Discuss catalytic oxidation of CH4.iv. What is Raney nickel and how it is prepared and why it is more effective than ordinary nickel.v. How Baeyers test is used to detect unsaturation in organic compounds.vi. Write best method of preparation of alkyl halide from alcohol.

vii. Briefly explain the reactivity of alkyl halidesviii. Differentiate between E1&E2reactions.

ix. First step of SN1&E1reaction is same while 2nddiffer explainx. Tertiary alkyl halides do SN1reaction and not SN2why.

Q.3. (a) What are SN reaction? Explain SN2reaction in detail with mechanism. (5)

(b ) Starting from suitable alkene prepare the following compounds. (5)

i. Halohydrin ii. Polyethene iii. Formaldehyde iv. Propylene epoxide v.Ethanol