General organic chemistry Questions and Answers

What are the products of phospholipase D degradation of phosphatidylcholine O A Phosphatidic acid phosphatidate and choline O B Diacylglycerol and phosphoethanolamine O C Phosphatidic acid phosphatidate and ethanolamine O D Diacylglycerol and phosphocholine

1 216 g Organic compound analysed by kjeldahl methodand NH3 evolved was absorbed in 100ml N H2SO4 Remaining solution was made upto 500ml by water 20 ml of this solution require 32ml N 10 NaOH for complete neutralisation Find N

In case of optically active alkyl halides SN1 reactions are accompanied by racemisation Can you think of the reason why it happens Actually the carbocation formed in the slow step being sp ybridised is planar achiral The attack of the nucleophile may be accomplished from either side of the plane of carbocation resulting in mixture of products one having the same configuration the OH

Question No 85 Single Correct A HCN KOH product B is A OH A CHO OH NH OH X OH CH NH i LIAH Bi ii H O CN A

81 180 Consider the following compounds CHO 1 ii iii keto enol tautomerism is observed in i and ii only i only iii only i and iii only B

O The Fischer projection formula that represents the following compound is A C CH H OH H OH HO H CH 3 OH H CH3 H OH H CH3 OH H C OH H OH H OH CH3 B D OH H CH3 HO H H OH CH3 HO HO H CH 3 H H CH3 OH

Statement 1 RCOCI RCO 0 and RCOOR all react with Grignard reagents to form 3 alcohols Statement 2 RCOCI reacts with R Cd to form ketones but RCO 0 and RCOOR do not react at all A B Both Statement 1 and Statement 2 are true and Statement 2 is the correct explanation of Statement 1 Both Statement 1 and Statement 2 are true and Statement 2 is not the correct explanation of

3 Which of the following is the correct order C C bond lengths among these compounds 1 CH O CH CH NO II CH CH NO III CH CH CH IV CH CH 1 I II II IV 2 IV III II I

What is the major E2 product formed in the following reaction Br H3CO A C H3CO Both A and B 11CH3 CH3 NaOC H5 B D H3CO No reaction CH Activate Windo

please tell what is leaving group in A C and D Question 39 Consider the following compounds A CH COOCH B CH a 8 0 8 04 C CH D CH C S C CH S 8 CH The correct order of rate of nucleophilic acyl substitution reaction is Options B A C D B C D A B D C A D B C A Solution Answer 3 Rate of nucleophilic substitution reaction x strength of leaving group

Which of the following is correct Only one correct answer A B C D CH CH OH CH CH OH I CH OH 1 CH C CH T CH OH C H C CH 573 K Cu 573 K Cu 573 K Cu 573 K CH CH CH CH CH CH C CH I CH OCH C H C CH3 CH

distance PO is equal to 1 R 2 3 R 3 2 R of this combination is 1 1D 2 9D 4 5 R GO0056 LENSES 7 Two convex lens of focal length 20 cm and 25 cm are placed in contact with each other then power 3 1D 4 9D

Alkyl halides can be obtained by all methods excepts CH3 CH OH HCI ZnCl B CH CH CH HBr C H5OH NaCl CH COOAg Br CCI h

54 Compound X reacts with diborane followed by alkaline hydrogen peroxide to form compound Y Y on reaction with a mixture of sodium bromide in sulphuric acid followed by bromobenzene and sodium in ether gives n pentylbenzene Compound X is 0 A B D

Holloway Julia 12 48pm 10 82 Identify each of the following as an acid base or salt and give its name 10 1 a H3PO4 b MgBr c NH3 d HClO2 e NaCl

5 Allylic and benzylic halides show high reactivity towards the SN1 reaction 7 For a given alkyl group the reactivity of the halide R X follows the same orde both SN1 and SN2 mechanisms R I R Br R Cl R F R A SN2 reaction proceeds with complete stereochemical inversion while a SNI

1 2 3 acidic order of acidity is 4 OH OH OH OH 66 66 CH at para CM3 1 hyprccenjingatican OH OH OH OH OH 66 66 CH3 OH CH3 OH OH CH3 CH3 CH3 OH CH OH CH3 CH3 OH CH3 OH

How come opt 2 be the answer What s wrong with opt 4 Please try to brief the underlying concept here 2 Most stable radical among the given options is 1 CH 3 CH 2 CH CH CH CH 4 CH C CH

When nitrogen gas is treated with hydrogen gas in the presence of a catalyst at 773 K ammonia gas is formed This reaction is in example of O Displacement reaction O Combination reaction Decomposition reaction O Double displacement reaction

The compound which will undergo nucleophilic addition reaction at fastest rate is CHO CHO OCH3 CH3 OCH3 CHO

Which reagent or sequence of reagents would bes accomplish the following synthesis OEt datio imited 1 i LIAIH4 ii H A 2 i NaBH4 SO4 iii conc H SO4 dil 3 i Na NH3 ii NaBH H A 4 i Mg Et O ii LIAIH iii H A

1 What is the correct reactivity order of electrophilic addition reactions in the following compounds 6 B IV III II I 1 A II IV I III 11 III C III I IV II IV C H D I II III IV

Using structural formula provide equations to show how you could synthesize the following compounds Reaction conditions and reagents must be included Multiple steps may be required 4 marks a 1 chlorobutane butanoic acid b cyclopentanol cyclohexane

Which of the following cannot be made by using Williamsons synthesis A B Methoxybenzene Benzyl p nitrophenyl ether C Methyl tertiary butyl ether D Di tert butyl ether

In the given sequence of reactions the products A and D are respectively OH A O conc HNO3 conc H SO4 Heat i NaOH ii CO heat B dil HCI 2 4 dinitrophenol and salicylic acid C picric acid and salicylaldehyde 2 4 6 trinitrophenol and phenyl salicylate O Opicric acid and 2 acetoxy benzoic acid CH3COCI CH3COOH pyridine D

Which of the following reactions is are correctly interpreted CI 1 CH CECH 2 equiv HCI CH CH CH CI i CH C CH Ph Ph C CCH II CH CEC Ph H O III CH CEC Ph Br IV O O CH HBr I only R O ho III and IV only O O I II III and IV I and II only Hg 2 H Br H Br CH H Br H Br H CH

Would you expect cyclohexane C H to be miscible with water Explain why or why not

a 2 b 4 c 5 d 6 6 Which of the following is not both a Bronsted Lowry acid and a Bronsted b H PO4 c HCO3 d H3O a HSO4 7 Which of the following compounds is a Lewis base a Hg2 b AlCl3 C CN d B OH 3 What is the conjugate acid of H C6H5O7 is a 6H5O73 b HC6H5O72 C H3C6H5O7 d H C6H5O7 Which of these salts would form an acidic aqueous solution h KCl NaNO c CrCl d NaBrO

A 17 10 g compound is made up of 5 900 g N and 11 20 g C What is the percent composition of carbon in this compound Your answer should have four significant figures

Q 3 Dentistry 0 4p each correct answer 1 Which of the following pair has dipole dipole forces d 1 H O a H S NH b CO CS c CCl4 H 2 Which of the following can form hydrogen bonds with HF d C H5OH a CH F b Na c C6H6 3 pH of certain orange juice is 3 What is the H concentration a 10 1 b 10 2 c 10 d 10 11 4 Identify the strongest base b Kb 103 Group a Kb 10 c Kb 10 d Kb 1011 5 Which of the following is the van t Hoff s factor for 2M of calcium bromide a 2 d 6 b 4 c 5

Given the below reaction aA bB cC dD The means Oa the reaction is impossible Ob the reaction is slow O c the reaction can go in the forward or reverse directic O d the reaction is fast

Which energy difference represents the forward activation energy of the reaction Energy O a A Ob B Odc A B C D Progress of Reaction A

d dbromonitrobenzene 6 Which of the following is NOT true about delocalized molecular orbitals in benzene a interaction of the unhybridized 2p orbitals in benzene leads to the formation of delocalized molecular orbitals b delocalized molecular orbitals are not confined between two adjacent bonding atoms c delocalized molecular orbitals actually extend over three or more atoms melay d electrons residing in any of these orbitals are not free to move around the benzene ring

If 10 0 moles of Al2O3 are reacted per the below reaction how many moles of oxygen gas are produced a 15 0 b 6 7 Oc 3 0 d 30 0 O e 6 0 2Al2O3 1 4Al s 30 g 4

At max how many electrons are in an s sublevel 02 06 O 10 O 14 4

24Mg and 24Mg2 are Oions isotopes different elements isoelectronic

A reaction is at equilibrium when a all motion stops b the concentration of the reactants is equal to the concentration of the the products Oc the limiting reactant has been completely consumed d the rate of the forward reaction is equal to the rate of the reverse reaction

Compound Benzoic acid Vanillin Mandelic acid trans Cinnamic acid Urea Functional groups Structures acid CooH COOH Aldehyel hydroxyl ether hydroxyl acid Cary amine ketone Ho O Au TOCF13 OH AN M N C NH i do OH

10 Which of the following is a major product of the dehydration reaction of 3 methylpentan 2 ol a 3 methylpent 1 en 2 ol b 3 methylpent 2 en 2 ol c 3 methylpent 1 ene d 3 methylpent 2 ene 11 Which of the following alkohols is the strongest acid a R COH b R CHOH c RCH OH 12 Finish the reaction a C H OK H b C H K 0 c C H OK H O d C H K H O C H OH KOH d CH OH

Classify carbon monoxide CO as an element compound or mixture element compound mixture

1 What is the IUPAC name for the structure shown below a 1 1 1 trimethylpentane b 1 1 1 trimethylbutane 2 General formula for alkynes is expressed by a CnH2n 2 b C Hzn 3 Which of the following is alkane a C H b CH O CH CH C CH CH CH CH c 2 2 dimethylpentane d 2 2 dimethylbutane C CHzna c CH14 Pentine d C H 2 d C H10

Two atoms with the following symbols are 18 9X 13 6X different elements isotopes Oions the same element and isotope the same element

What is the mass number for the following isotope How many neutrons does the following element have 345 34 18 neutrons 34 34 neutrons 34 16 neutrons O16 16 neutrons

Which functional group s would be added to 1 methylcyclohexene using the reagents below Br H O ketone and aldehyde hydrogen bromine and hydrogen bromine and hydroxyl ketone hydrogen and hydroxyl Obromine hydroxyl aldehyde

17 What is the outcome of the reaction carboxylic acid with alcohol a amide b alcohol ester d anhydride 18 Following compound is named as a N N dimethylformamide c N N methylformamide CHO NIC CH C N CH b N N dimethylacetamamid N N methylacetamamide

How many electrons does the species represented by the following symbol have 50Sn4 118 O 50 O 46 O 54 68

Calculate the theoretical mass percentage of oxygen in potassium chlorate KC1O3 Show all steps include measurement units and follow the significant digits convention

19 The main organic product of acyl chloride hydrolysis is a ester b amide carboxylic acid d alcohol 20 Which product would you expect from the reaction of ethyl ethanoate with H Or a ethanoic acid ethanol acetamide ethanol only ethanol c d only acetic acid

Which of the following subshells is greatest in energy O5s 3s 4p 4d

Indicate the number of protons neutrons and electrons in the following atom O7 protons 8 neutrons 10 electrons O7 protons 8 neutrons 4 electrons 15 protons 3 neutrons 1electrons 8 protons 7 neutrons 11 electrons