Chemistry Questions and Answers August 27, 2020

The cis isomer of 1bromo4tertbutylcyclohexane than the trans isomer. Explain why the cis isomer reacts faster. For full credit, your answer should include one or more diagrams. undergoes E2 elimination 1000 times faster

(a) A kinetic study of the reaction between an alkyl bromide (RBr) and a nonnucleophilic hase (base) provided the following data RBr (ml) 1 1 2 3 base (m) 1 2 4 4 Rate of reaction () 6 6 12 18 Write the rate law for this reaction. Include a numerical value and units for k. Clearly identify the order of each reactant.,(b) Did this reaction proceed

(b) H,(a) Indicate whether or not you would expect to see a significant amount of reaction according to each mechanism type by circling yes or no. In the bottom row of each table, justify your answer by For each yes, drawing the organic product(s) that will be observed. . For each no, briefly explaining why you expect littletono reaction. CH

Propose a reasonable reaction mechanism for the following reaction,H3C CH3 X . CH3 HBr HC CH3 2 H.C CH3 to

Compound B HO Compound A HSO4 HO Compound C,H NMR analysis of Compound A (CH,CI) gives a spectrum with one singlet at 1.6 ppm. When Compound A is reacted with water, a mixture of two products is formed H NMR analysis of Compound B gives two signals 1.3 ppm and 2.0 ppm H NMR analysis of Compound C gives two signals 1.7 ppm and 4.7 ppm. If

(a) Consider the following reaction mixture HC HH H Br Draw the major organic product obtained if the reaction proceeds according to an SN2 mechanism. Briefly explain why this isomer is obtained.,(b) Draw the major organic product obtained if the reaction proceeds according to an E2 mechanism at high temperature. Briefly explain why this isomer is

5Bromo1,3cyclopentadiene is a bad substrate for SN1 or El reactions. Why For full credit, your answer must include the structure of 5bromo1,3cyclopentadiene and any other relevant structures. If you need a hint, start drawing the mechanism for an Syl or El reaction involving 5bromo1,3cyclopentadiene.

(a) (b) For each of the following multistep processes, draw the major organic product of each step in the appropriate box. Br 00 NaN3 DMF DMF H, PdC ethanol NaOH DMF

HC... H o Ph H CHOH,Draw a reasonable mechanism for the following reaction and draw the final product in the box provided. Clearly show any relevant stereochemistry of the final product.

With reference to the reaction mechanism, explain the regioselectivity of this reaction.,Draw the major organic product of the reaction between 1,3dipropylbenzene and acetyl chloride (CH3COCI) in the presence of aluminum chloride.

Draw the product of each reaction. 1. 1 equiv. NaH 2. 1 equiv. CHI OH,OH 1. 2 equiv. NaH 2. 1 equiv. CHI,OH H, 10 PdC ethanol,excess HBr

Explain how you could use spectroscopy to differentiate between this pair of isomers. Your answer should make reference to at least two types of spectroscopy (IR, H NMR or 13C NMR). Note that you are not being asked to completely describe each spectrum. You are being asked to point out key differences between spectra of the two isomers. Be

Linezolid is an antibacterial drug marketed by Pharmacia as Zyvox. Fill in the blanks in the last few steps of the synthesis of linezolid (shown below). Some reaction conditions have been simplified for clarity. oph. OH linezolid CHSOCI EtN, CHCl Note that CH3SOCl MsCl 2k NaN, polar solvent heat H 10 PdC solvent

(b) Draw the mechanism for Step 2 of this synthesis. Please abbreviate C6H4SONH as Ar,Step 1 Step 2 One synthesis of celecoxib (an antiinflammatory marketed by Pfizer as Celebrev shown below. olda CF3 050 HN CF NaOCH, CH,OH, reflux H NH (a) Draw the mechanism for Step 1 of this synthesis. 1 equiv. HCI ethanol, reflux 050 HN CF LCF, celecoxib

Choose any three of the molecules below and propose a synthesis of each. Your organic reactants must be stable compounds that contain no more than five carbon atoms. They may be hydrocarbons, alkyl halides or alcohols and may contain CC or CC bonds. You are also allowed to use benzene, bromobenzene or phenol. If you wish to use an organic

Compound A has the molecular formula CsH6 and has a C NMR with three signals. It dimerizes readily. When treated with a strong base, anion A is generated which gives only one signal on its 3C NMR. Draw compound A.,Draw anion A and explain why it only gives one signal on the NMR.,Draw the product(s) formed when A reacts with 1 equivalent of

Find the evidence and conclusion of the following compounds characterizations.

IR 13C NMR H NMR Evidence C6H1003 Conclusion DU 2

CI B (a) NO NO You wish to prepare various isomers of chloronitrobenzene from benzene. For simplicity, they have been labeled A, B and C CI (c) . A B Consider how H NMR can be used to identify which product(s) are made from each reaction. For each isomer, complete the table provided to clearly indicate The relative integration of each peak The

(a) (b) (c) (d) Br Dihydropyran can be used as a protecting group for alcohols O dihydropyran he catalytic H H dihydropyran HO On the previous page, draw the missing intermediate products in the boxes provided. Why is a protecting group necessary for this reaction sequence to work 2 marks Grignard reagents cannot be formed in the presence of

Explain why you cannot prepare a ketone by reacting an ester with a Grignard reagent. Your answer should include a mechanism. You may choose any ester and any Grignard reagent to illustrate your point.

Consider the molecule below OCH3,(a) What compounds would you react to prepare this compound using a normal DielsAlder reaction,(b) What compounds would you react to prepare this compound using an inverse electron demand DielsAlder reaction,(c) Is the compound above the exo product, the endo product, both or neither Explain. Your answer should

(b) (d) The following page contains spectra for Unknown X. Identify Unknown X based on these spectra. Draw your answer in the box provided below. Use this page to explain your logic (including how you determined the molecular formula). On both NMR spectra, assign as many peaks as you can by numbering the peaks from left to right, redrawing Unknown

CI .,Show the mechanism for the reaction below and draw the major organic product. Clearly show any relevant regiochemistry andor stereochemistry in the product.

You wish to perform the following reaction,Why can you not use an SN1 approach,Why can you not use an SN2 approach,How would you do it Include specific groups to replace X and Y, and identify any other necessary reagents.

Explain why an a synthon is usually a better choice than a d synthon. Your answer should include an example of each.

Consider the following sequence of reactions. There is no workup done between reactions. NaOCHs CHOH HCI, HO heat FO 6 marks

Use an argument based on hardsoft principles to explain why NaH and LiAlH4 react differently with acetone NaH O VS. LiAlH4 THF Your answer should include a mechanism for each of the reactions shown above. THF O

One of the first steps in the synthesis of sildenafil (Viagra) is shown below. Eto of HN NH Propose a reasonable mechanism for this reaction. HO Eto

How would you make each of the molecules below Your answers should take the form of a retrosynthetic analysis followed by cnemical equations for the reactions in the synthesis itself. Show all required reagents, and number steps within a reaction if order of addition is important. You may use any reagents that you could reasonably expect to be

(a) The main natural synthons are a, d and a. Explain why each of these synthons has natural reactivity. Each explanation should include an example. a synthon,(b) d synthon,(c) a synthon

(c) Propose a reasonable mechanism for the second step in the synthesis of BMTB. (shown below),2bromoNmethylthiazolium bromide (BMTB) was developed as a peptide coupling agent that would be better at coupling sterically hindered amino acids better than the alternatives that existed at the time. It was made in three steps from chloropropanone (aka

The structure of penicillin is shown below. Identify one disconnection that you would make if you were tasked with synthesizing penicillin. Explain your choice. Show the corresponding forward reaction for that step. DO NOT TRY TO PROPOSE A WHOLE SYNTHESIS OF PENICILLIN H s H

Supercritical carbon dioxide can be used to extract caffeine from coffee and tea. Coffee beans are soaked in water then put in a sealed vessel with carbon dioxide which is pressurized to approximately 70 atm (70 times atmospheric pressure). Once the caffeine has dissolved in the supercritical carbon dioxide, the solution flows to another chamber

We studied two reactions in which a ketone or aldehyde reacts with an ylide. For each reaction draw the final organic product, show the mechanism, and clearly indicate the driving force pushing the reaction forward.,(a) H H Ph Ph CH Ph,(b) H H HC H CH

Propose a reasonable mechanism for the reaction below. One intermediate is shown. 181 EN s EN

If you were going to develop a retrosynthesis for artemisinin, what would be the first disconnection you would propose Provide at least two reasons for your choice.

From the data given, work out the rate law for the following overall reactions. H3CBr CH3SH H3CSCH3 HBr,What is the rate law for the following overall reaction

Sketch a reaction profile diagram for the following process, used to prepare alkyl bromides from alkenes. 1) HC H3C 2) HC H3C CH H CH3 CH HBr Br slow fast HC CH3 96 CH H3C HC CH3 34 Br CH H3C Br

What are the different mechanisms of regulation of blood pH.

Extraction of copper from copper pyrite CuFeS2 involves (a) Crushing followed by concentration of the ore by froth-floatation (b) Removal of Iron as slag (c) Self-reduction step to produce blister copper following the evolution of SO2 (d) Refining of blister copper by carbon reduction

Upon heating with Cu2S, the reagent(s) that give copper metal is/are: (A) CuFeS2 (B) CuO (C) Cu2O (D) CuSO4

Which among the following statement(s) is(are) true for the extraction of aluminium from bauxite (a) Hydrated Al2O3 precipitates when CO2 is bubbled through a solution of sodium aluminate. (b) Addition of Na3AlF6 lowers the melting point of alumina. (c) CO2 is evolved at the anode during electrolysis. (d) The cathode is a steel vessel with a

Galena (an ore) is partially oxidized by passing air through it at high temperatures. After some time, the passage of air is stopped, but the heating is continued in a closed furnace such that the contents undergo self-reduction. The weight (in kg) of Pb produced per kg of O2 consumed is ______. (Atomic weights in g mol-1 : O = 16, S = 32, Pb =

Formic acid (HCOOH) is a weak acid used as preservative and antibacterial agent in livestock feed. Which of the following aqueous solutions of HCOOH has the highestdissociation in aqueous solution The K, for HIO is 1.8x 10 4 at 25C. Hint this question does not necessarily need any math to be answered. O a. 1.2103MHCOOH Ob. 4,510 MHCOOH O c. all

Consider a buffer composed of aqueous solutions of HCN and KCN. What is the net ionic equation for the reaction that occurs when a small amount of LiOH is added to the buffer O a. CN (aq) OH(aq) 02(aq) HCN(aq) O b. HO(aq) OH (aq) 2HO(1) O c. HCN(aq) LiOH(aq.) LiCN(aq) HO(l) O d. HCN(aq) OH(aq.) CN(aq) HO(1)

Show how you could carry out the following syntheses (a) (b) (c) (d) from from from from Br

In the current year, Peeta Company reported book income of 140,000. Included in that calculation was 50,000 for entertainment expenses and 40,000 for federal incometax expenses. Provided these are the only items affecting Schedule M1, what amount should be reported on Schedule M1, Line 10, as income O 230,000 205,000 O 140,000 In the current year,

Write the following reactions by explaining the mechanism Explain the stereochemistry at each step. Indicate whether the products are optically active and their stereochemical relationships with each other. a) b) H NH OH NH HO PCC CHCl KOHHO Heat Ph3PCH

Calamine, malachite, magnetite and cryolite, respectively are: (a) ZnSO4, CuCO3, Fe2O3, AlF3 (b) ZnSO4, Cu(OH)2, Fe3O4, Na3AlF6 (c) ZnCO3, CuCO3Cu(OH)2, Fe3O4, Na3AlF6 (d) ZnCO3, CuCO3, Fe2O3, Na3AlF6

Sulfide ores are common for metals. (a) Ag, Cu and Pb (b) Ag, Cu and Sn (c) Ag, Mg and Pb (d) Al, Cu and Pb

The carbon-based reduction method is not used for the extraction of: (a) Tin from SnO2 (b) Iron from Fe2O3 (c) Aluminium from Al2O3 (d) Magnesium from CaCO3

To what temperature (in C) must a balloon, initially at 23C and 9.4 L, be heated in order to have a volume of 15.7 L 216C 4 494C 177 C 38 C 202 C

Below are two resonance structures for formic acid. Part A oxygen atom is more electronegative than the C and H hydrogen atom is more electronegative than the C and Explain why the first structure is the best resonance structure. Match the items in the left column to the appropriate blanks in the sentences on the right. left zero formal charge

Fill in the columns of the data table. Be sure to show calculations where they are called for, and to include the correct units for each entry. Mass of calorimeter cups empty Mass of calorimeter cups 50. mL of d. HO Mass of cool water in cups (show calculation) Initial temperature of cool water Initial temperature of heated water prior to mixing

2. (a) (ii) The accompanying data were obtained in a slope ratio investigation of the complex formed between and 1cyclopentene 1 di thiocarboxylic acid (CDA). T he measurements were made at 530nm in 1.0 cm cells. (1) CCDA 1.00 x M M 5.00 x 1.20 x 3.50 x 5.00 x 6.00 x 7.00 x 0.051 0.123 0.359 0.514 0.616 0.719 1.00 x M CCDA,M 9.00 x Page 2 of 6

Decarboxylation of organelementformats leads to 1 alcohols. Select one True False

(ii) Calculate the difference in arrival time at the detector for two singly charged ions in a time of flight mass analyzer, one with mz 1252.054 and another with mz 1253. 138 accelerated by a potential of 20kv in a 1.750m flight tube. IV 1, IJ 1kg ICIAS, e 1.602 x C IU 1 amu 1.6605 x kg IT 1 kg 1 kg Give your answer in nanosecond. 4 marks

Determine the amount of silver in the sample solution in ppm. 1 marks (d) (i) A concentration cell having two electrodes of a metal x, one dipping into an 0.125M solution of one of its salt and the other into an 0.0125M of the same salt has an emf of 0.014V at 298k. Calculate the ratio of the mean activity coefficients of ions given that, the

3. (s) cd O N (a) (i) Determine the degree of hydrolysis of a niline hydrochloride in 40 solution of salt at 25 dE dT Pt H H0 N (latm) 40 Ecell 0.4300V 2d S04 (v) ), change in entropy ( 0 c from the following cell data at 25 ESCE 0.242V Calculate the hydrolysis constant of the salt. 3 marks (ii) Derive an equation relating enthalpy change and the

(d) In a Hittorf cell with silver electrode contains a 0.01 molal Ag NO3 solution and a silver coulometer is connected in series. Electrolysis is continued for some time. Analysis after electrolysis, shows. (i) 32.10 mg of Ag is deposited in the coulometer. (ii) 20.09 gm of solution of the anode chamber of the Hittorf cell contains 39.66 mg of 6

The retention times of a sample containing substances A and B in a 45 cm long column were (A) 24.40 min, respectively; (B) 25.80 min. The retention time of a substance not retained in this column is 1.20 minutes. Widths of the peaks (W) of types A and B: 1.17 minutes for A; For B it is 1.27 minutes. According to this: a) Type B retention

(b) Write the stepwise mechanism for biosynthesis of apinene from geranyl pyrophosphate (6 Marks) ter apinene

Identify the acetate units in each of the following compounds . agg 0 (a) (c) HO. (b) . 0

(c) A volatile plant product M, C8H140, has strong IR absorption at 1717 cm. It possess H NMR signals at 8H 1.65 (3H, s), 2.15 (3H, s), 2.4 (4H, m) and 5.20 (1H, t). On ozonolysis, compound M gives, among other products, propanone, and on treatment with iodine and alkali it gives triiodomethane (iodoform). What structural formula can be obtained

Alkaloid G, C8H13NO, is a tertiary base. It has IR absorption at 3500 cm and H NMR signals at 8 3.0 (5H, m), 3.8 (2H, s) and 5.4 (1H, t, J 7 Hz). It can be oxidized under mild conditions with MnO to give compound H, C8H1NO, which had an IR absorption at 1680 cm and a UV absorption at 229 nm. Compound H formed a deepred dinitrophenylhydrazone. On

(d) Indicate the biosynthetic structural units acetate, C (methionine), Cs (isoprene), C6C3 (shikimate) that form the carbon skeletons of the following compounds. Some of these compounds may be formed by combination of more than one pathway (5 marks) 10 (a) (c) Me. OMC COH CHOH OH (e) HO (b) (d) MeO MeO OMe Me NMC (e) Describe the biosynthesis of

(f) Propose a plausible stepwise synthetic route to each of the following complexes. (6 marks) CH5 (i) (CO),WC OCH 3 CH3 (ii) (PPH3)2(NO)CIOS CH3 H (iii) (CO),Moz CH

(b) Complexes of formula Rh(CO)(phosphine)2Cl have the CO stretching bands shown below. Match the infrared bands with the appropriate phosphine. Justify your answers. (4 marks) Phosphines P(pC6H4F)3, P(pC6H4Me)3, P(tC4H9)3, P(C6F5)3 v(CO), cm 1923, 1965, 1984, 2004 (c) Propose a mechanism for the catalytic conversion of but2ene to butane using the

QUESTION ONE 30 MARKS (a) Write the IUPAC name of each of the following organic compounds (6 marks) (i) () (VI) (b) Write equations for synthesis of pentanal from each of the following starting materials (4 marks) (1) CHCHCH CHCHOH (iii) CHCHCH.C,CO,CH (ii) CH3CHCHCHCHCH (iv) CH3CHCHCHCH2

(d) Design a plausible stepwise method of effecting the following transformation (3 marks) ye (e) Write a detailed mechanism for the following reaction (7 marks) l R R observations 01 OCHCH 2 CHOH HO HCO R OCH3 R LOH (f) Explain the following

(i) Amides are far less basic than amines (2 marks) (ii) Aromatic amines are weaker bases than the corresponding nonaromatic amines (2 marks) (iii) Ketones have higher boiling points than alkanes of similar molecular weights (1 mark)

QUESTION THREE 20 MARKS (a) Write the name of each of the following organic compounds (6 marks) (i) h holl (iv) (V) HO OH (b) Describe, with the aid of suitable examples, four methods that can be used for laboratory preparation of amines (8 marks) CH (c) Design a plausible synthesis of each of the following compounds using diazonium salts as

(iii) You have measured the blank for a determination of arsenic in food samples by hydride generation atomic fluorescence spectrometry. The blank values are 0.23 ppb, 0.14ppb, 0.16ppb, 0.28ppb,0.18 ppb, 0.09 ppb, 0.10 ppb, 0.20 ppb As calculate. LOD at 95 and 99 confidence levels. 4 marks (1) (II) Based on your answer in (iii) (I) Calculate the

(Ch. 3.5) Given the balanced equation below, calculate the number of moles of solid bismuth produced from the complete reaction of 4.04 grams of carbon. BiO3(s) 3 C(s) 2 Bi(s) 3 CO(g) (Report 23 decimal places. Enter only the numerical portion of the answer)

b) A drug analysis is performed with gas chromatographymass spectrometry (GCMS) and requires the use of reliable standards. The lab purchases a 1.0 ml commercial standard that is certified to contain the drug of interest at a concentration of 1.00 mgml with a reported uncertainty of 1.0 . To prepare the stock solution for calibration, an analyst

The bioavailability of morphine is reported to be between 20 and 30. A common pharmaceutical preparation of morphine is in the form of 40 mg tablets that contain 40 mg of the drug. I) If a lady takes two pills at the same time, how much morphine will be in general circulation (3Marks) Assume the lady weighs 145 lb and takes the tablets of

b) A trainee in forensic chemistry laboratory is tasked with determining the concentration of cocaine in a white powder. The following data is obtained from a trainee 10 replicate analyses. The true value of mean is 13.2 0.1 Sample 1 2 3 4 5 6 7 8 9 10 Value 12.7 13.0 12.0 12.9 12.6 12.3 13.2 11.5 15.0 12.5

a) As part of a methodvalidation study, three forensic chemists made ten replicate injections each in a GCMS experiment and obtained data for area counts of a reference peak. Injection No. 1 2 3 4 5 6 7 8 9 10 A 9995 10035 10968 10035 10376 10845 10044 9914 9948 10316 B 10640 10118 10267 10873 10204 10593 10019 10372 10035 10959 C 9814 10958 10285

A student is trying to figure out the density of an unknown gas in a round-bottomed flask in a lab. The flask weighs 103.89 grams by itself, and the condensate and flask together weigh 105.20 grams. The flask can hold a total volume of 250 mL. 1) What is the unknown gas's density? 2) How much does one mole of the unknown gas weigh?

QUESTION (i) (a) ONE (20 MARKS) In paper chromatographic separation of silver, lead and mercury, the solvent front was 18cm while fronts due to these elements were respectively 16, 12 and 16cms. Calculate Re value of all metals 2 marks (ii) In a particular thin layer chromatographic separation, the Revalue of an unknown compound was 0.809. The

These results were obtained Y 12.5 cm Xa10.0 cm WA 1.0 cm Xa8.5 cm WB0.9 cm Calculate the Retardation Factor (Re) factor for both A and B 2 points Retardation factor (R) The ratio of the distance traveled by the center of the spot to the distance simultaneously trav eled by the mobile phase and is used in planar chromatography. Using the symbols

(III) Establish the relationship between the selectivity factor and the Rr of the 5 marks two compounds. Calculate its numerical value

(iii) An electrophoresis analysis in free solution (capillary electrochromatography) calls for the use of a capillary of 32 cm and with effective length of separation 24.5 cm. the applied voltage is 30kV. Under the conditions of the experiment the peak of a neutral marker appeared upon the electropherogram at 3 min (1) Calculate the

(b) A mixture of proteins is separated on a column with a stationary phase of carboxymethylated cellulose. The internal diameter of the column is 0.75 cm and its length is 20cm. the dead volume is 3 ml. the flow rate of the mobile phase is 1mlmin. the pH of the mobile phase is adjusted to 4.8. Three peaks appear upon the chromatogram corresponding

The method of internal normalization was chosen to determine the mass of a sample comprising a mixture of four esters of butanoic acids. To this end, a reference solution containing known mass of these esters led to the following relative values of the response coefficients often butanoates of methyl (ME), of ethyl (EE) and of propyl (PE), all

(d) Assume that in extraction from water into toluene analyte A has the distribution ratio D10. A 20ml portion of an aqueous solution of A is extracted with toluene. Which of the following procedure will result in the most efficient removal of A from the aqueous phase into toluene One extraction with 40ml of toluene Two extractions with 20ml of

2. Carnot Engine A uses 1 mol monatomic ideal gas as working medium. The temperature for isothermal expansion is 47o. The temperature for isothermal compression is To. The starting volume for the isothermal expansion is Vo. The starting volume for the isothermal compression is 64Vo. (See the figure below.) For each Carnot circle, Engine A exerts

(e) and (f) marks) Predict the structure of a molecule with a molecular formula CH5O peak at mz 72 an IR absorption at 1725 cm (2 marks) Explain the observation in IR spectroscopy that CC bond absorbs at 1650 C C bond absorbs at 2250 cm and (2

(b) The melting points of metals A and B are and respectively. They form an intermetallic compound C, containing 75 percent of A which melts at. Mixtures containing 20 percent and 90 percent of A melt at constant temperatures at and respectively. marks marks mark (i) Draw an approximate equilibrium diagram and label each area to indicate the

2. marks marks (a) (1) (ii) Derive the general expression of fugacity for liquids at constant temperature. 2 Liquid chlorine at has a vapour pressure of 0.77M pa, fugacity 0.7M pa and molar volume kg mole. Calculate the fugacity at 10 2 marks mpa and (iii) A terinary gas mixture contains 20 mole A, 35 mole B and 45 mole C at 60 atmand. The

(b) (i) (ii) Deduce whether the equation given below is thermodynamically consistent X mole fraction Derive an equation for dependence of enthalpy change on temperature for the reaction. Coefficients in heat capacity equations Substance Temperatur e range K 50100 50100 Cgraphite 50400 3.6297 1.7943 3.259 1.356 1.30031 21.18944 0.6579 1.502

Is it true that water is in the liquid as well as the gaseous state at 100C Options 1) True 2) False

Is it true that carbonate ore gives carbon dioxide on treatment with dilute HCI Options 1) True 2) False

Which of the following sets of phenomena would increase on raising the temperature Options 1) Diffusion, evaporation, compression of gases 2) Evaporation, compression of gases, solubility 3) Evaporation, diffusion, expansion of gases 4) Evaporation, solubility, diffusion, compression of gases

Shivam visited an LPG unit and found that the gas can be liquified at specific conditions of temperature and pressure that isare Options 1) High temperature and high pressure 2) Low temperature and low pressure 3) Low temperature and high pressure. 4) High temperature and low pressure.

The increasing order of forces of attraction in air, water, and sugar is Options 1) Air Water Sugar 2) Air Water Sugar 3) Sugar Water Air 4) None of these

Write the formulae of all the compounds below that are highly soluble in water. BaCOs Pb(NO3)2 NaCrO4 Cas(PO4)2

(ii) (1) An actinometer uses a solution of in which is reduced and the oxalate ion is oxidized. Assuming at 310nm, calculate the intensity of the incident light which produces mole 36.5 min. (II) of in The same light source is used to irradiate a sample of for a period of 15.2 min. if the quantum yield of is 1.0 and that if CO is 2.0, determine

(c) An aqueous solution of a compound A of concentration moleslitre absorbs 50 of incident radiation in a cell length 1cm and another compound B of concentration moleslitre absorbs 60 of the incident radiation at a particular wavelength. Calculate the percentage absorbed y a solution containing moleslitre of A and B each in the same cell at the

(a) (i) (b) disappearance of A is given by the equation (ii) A undergoes two simultaneous reactions to produce B and C according to show that, the observed activation energy for the (i) . where K is expressed in litre mol1 min1. Calculate energy of activation, and the halflife period at 20C when the initial concentration of base and acid are each