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Chemistry Paper VII Inorganic Chemistry Previous Year Question Paper Year 2006 : IIIrd Year

Q. 1. (a) Write the names of the following complexes according to IUPAC system of nomenclature :
(i) [Co (en)2 (ONO) Cl] Cl
(ii) [Co(NH3)6][CoCl6]

(iii) Image no.4

(iv) [(CH3)4 N] [Rh (NH3)2 (SCN)4]
(v) [Pt (NH3) Py Cl Br].

(b) Write the formulae of the following complexes :
(i) Dichlorobis (methylamine) iron (III) chloride;
(ii) Hexaammnine Chromium (II) hexafluorocobaUate (III).
Answer :

Q. 2. (a) Write all possible isomers for a complex of the type M (AA)2 B2±n.

(b) The compound Ir Br3.4H2O contains only one Cl- ion that will be precipitated immediately upon addition of Ag+ ions. Draw the structure on the basis of Werner’s theory.

(c ) The complex ion [MnBr4]2 and [Ni (CN) 4]2- are found to be paramagnetic and diamagnetic respectively. What is the geometry that can be assigned to these complex ions on the basis of Valence Bond Theory ?
Answer :

Q. 3. (a) What is green house effect ? How does it affect the global climate ?

(b) A black-coloured compound of manganese (A), when fused with KOH under atmospheric oxygen formed (B), a green coloured compound. (B), on electrolytic oxidation in alkaline medium gave a purple coloured solution (C) which on treatment with cone. H2SO4 gave green oily liquid (D). Identify A to D and give the sequence of reactions.
Answer :

Q. 4. (a) What happens when (Give chemical equations) ?

(i) A 30% solution of H2O2 is added to an alkalin’e solution of K2CrO4;

(ii) Cuprous Chloride is heated with acetylene,

(iii) CoCI2 is treated with KNO2 in the presence of ace tic acid.

(iv) Xenon and fluorine are mixed in a sealed vessel a 673 K in 1 : 20 ratio.

(b) Explain the industrial preparation of superphosphate of lime.
Answer :

Q. 5. (a) Complete the following reactions :
NH3(1)
(i) AgNO3+KNHz ——————-
SO2(1)
(ii) SOCI2+Cs2SO3 ——————-
NH3(1)
(iii) NH4NO3+ KNH2 ————–
SO2(1)
(iv) CH3COOAg+ SOCI2 —————

(b) How will you distinguish between the following pairs of somers ?

(i) cis and trans [Pt(NH3)zCI2]

(ii) [Co (NH3)5 SO4 ] I and [Co (NH3)51] SO4.
Answer :

Q. 6. Account for the following :
(i) The density of the third transition seris elements is almost twice that of the second transition series elements.

(ii) Solubility of noble gases in water increases as their atomic number increases.

(iii) Though transition elements possess very, high electrode potential but they are not good reducing agent.

(iv) TiO2 is colourless whereas Ti2O3 is coloured.
Answer :

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Chemistry Paper IX Physical Chemistry Previous Year Question Paper Year 2005 : IIIrd Year

Q.I. (a) A first order reaction is 15% complete in 20 minutes. How long will it take to be 60% complete ?

(b) Write cell reaction and calculate E° for-the given cell
Cd/Cd2+||Cu2+/Cu

Image no.3

(c ) When irradiated with light of 5000 Å wavelength, 1 x 10-4 mole ofasubstance is decomposed. How many photons are absorbed during the reaction if its quantum efficiency is 10.00

(d) Write down the number of phases, number of components and calculate the degree of freedom for the following equilibrium:
CaCO3(s) – CaO(s) + CO2(g)
Answer :

Q. 2. (a) Enumerate the different methods for determining the order of a reaction. 5
(b) At a certain temperature, the half life period for the decomposition of ammonia in contact with tungsten were as follows:
Pressure (mm of Hg) 50 100 200
Half life period (Relative) 3.52 1.82 ‘ 0.93
Find the order of the reaction,
Answer :

Q. 3. (a) What are concentration cells ? Derive the expression to calculate e.m,f. of a concentration cell without transference. 4
(b) The e.m.f. of the cell
Pb/PbCI2 (s) KCl/Hg2CI2(s)Hg
is 0.5357 V at 298 K and increases with temperature by 1.45 x I0-4 VK-1 Write the cell reaction and calculate ΔG, ΔH, ΔS.
Answer :

Q. 4. (a) What is Lambert’s Law? How has it been extended by Beer ?

(b) When propionaldehyde is irradiated with light of X= 3020 A, it is decomposed to form carbon monoxide.
CH3CH2CHO + hv -> CH3CH3 + CO

The quantum yield for the reaction is 0.54. The light energy absorbed is 15000 erg mol-1 in a given time. Find the amount of carbon monoxide formed in moles in the same time.
Answer :

Q. 5. (a) State the phase rule and define the terms phase, component and degree of freedom by giving examples to illustrate them. 3

(b) Discuss the FeCI3 – H2O system with the help of the phase diagram. Mention the various stable hydrates formed in this system.
Answer :

Q. 6. Write short notes on any two of the following:
(a) Absolute theory of reaction rates;
(b) Applications of Nernst’s distribution law;
(c ) Potentiometric titrations.
Answer :

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Chemistry Paper VIII Organic Chemistry Previous Year Question Paper Year 2005 : IIIrd Year

Q.I. (a) What is mutarotation ? Explain the formation of two anomers of glucose?

(b) How will you synthesise an aldopentose from aldohexose ?

(c ) Give the open chain and cyclic structure of D-fructose ?
Answer :

Q. 2. (a) Explain briefly
(i) Zwitter lon
(ii) Secondary structure of proteins

(b) Give the Sanger’s method for determination of N-terminal residue analysis of a peptide ?

(c ) What is the difference between essential and non-essential amino acids. Give one example of each ?
Answer :

Q. 3. (a) How will you synthesis α-Napthalene sulphonic acid and β-Napthalene sulphonic acid from napthalene ? 2

(b) Explain why pyridine is more basic than pyrrole ?

(c ) Image no. 2

(d) Explain the formation of glucosazone from glucose.
Answer :

Q.4 (a) Give the synthesis of Terylene or Dacron ?

(b) How will you synthesise
Acetylene—»Polyacrylonitrile 2

(c ) What are the monomers involved in the formation of following polymers ?
(i) Nylone6,6
(ii) Polyurethane 2

(d) How the structure of naphthalene was established?
Answer :

Q.5. (a) GiveamethodofpreparationofMalachitegreen.Give its uses. 3

(b) Why certain objects appear coloured ? Explain the concept of colour and constitution. 3

(c ) Why Edam’s method for determination of N~terminal residue analysis is more advantageous over Sanger’s method.
Answer :

Q. 6. Write short notes on :
(a) BHC
(b) Paracetamol
(c ) Chloroquine
(d) Isoelectric point
Answer :

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Chemistry Paper VII Inorganic Chemistry Previous Year Question Paper Year 2005 : IIIrd Year

Q. 1. Fill in the blanks of any nine of the following :
(i) (Co(en)3|3+ shows……………………isomerism.
(ii) …………………..is an example of a substance that causes eutrophication.
(iii) CuSO4 is………………..(attracted/repelled) by magnetic field.
(iv) The main pollutant responsible for green-house effect is…………………..
(v) NO~2 is an example of……………………….(ambient/ bidentate) ligand.
(vi) NH4 Cl is…………………(more/less) soluble than NaCl in liquid ammonia.
(vii) The geometry of XeF6 is……………………….
(viii) According to valence bond theory, K4 [Fe(CN)6] is a …………………………(inner sphere/outer sphere) complex.
(ix) Number of peroxo groups in CrO5 is……………………..
(x)…………….. is an example of a fertilizer containing both nitrogen and clacium.
Answer :

Q.2. (a) Name the following complexes according to the FUPAC system:
(i) [Cu(NH3)4(en)]SO4
(ii) [Co(NH3)4(SCN)2]CI
(iii) [Co(NH3)3 Cl2 Br]

(iv) Image no.1

(b) Write the formulae of the following complexes:
(i) Triamminetrichlorocobalt(iii)
(ii) Tetrammineplatinum (II) tetrachloroplatinate (1I)
(iii) Tetraquadibromochromium (III) ion
(iv) Tetrakis (trifluorophosphine) nickel (II).
Answer :

Q. 3.’ (a) Write chemical equations for the reaction of:
(i) Sodium nitropruside with sodium sulphide
(ii) Potassium permanganate with hydrogen peroxide, under acidic conditions
(iii) Potassium ferricyanide with ferrous ions. 1×3
(b) Explain why transition metals show variable oxidation states.
(c ) What is the root cause of acid rain ? Highlight one of its consequences.
Answer :

Q. 4. (a) Explain the phenomenon responsible for colour of potassium dichromate.
(b) Describe the preparation of potassium permanganate.
(c ) Why do chromium and copper have unexpected configurations ?
(d) What happens when:
(i) XeF4 react with water?
(ii) XeF2 react with HCI?
Answer :

Q. 5. (a) Write self-ionization equations for liquid ammonia and liquid sulphur dioxide.

(b) Indicate the reaction of:
(i) PCI5 and SO2 in liquid sulphur dioxide solvent,
(ii) NaNH2 and ZnCl2 in liquid ammonia solvent. 2

(c ) Why do bidentate ligands more stable complexes than monodentate ones ?

(d) Give the postulates of Werner theory.
Answer :

Q. 6. (a) On the basis of valence bond theory, find out the number of unpaired electrons in [Cr(NH3)6]3+ and [Ni(NH3)6]2+complexes. 3

(b) Depict the stereoisomers of [Co(en)2Cl2]+ indicating the techniques used to distinguish these.

(c ) Give the preparation of superphosphate of lime.
Answer :

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Chemistry Paper V Organic Chemistry Previous Year Question Paper Year 2006 : IInd Year

Q. 1. (a) The compound A, C7 H8, on treatment with methylchloride and aluminium chloride, yields a mixture of two isomers B and C, C8 H10, which are oxidized by potassium permanganate to the isomeric acids D and E, C8 H6 O4, respectively. Whereas D is unaffected by heat, E gives F, C8 H4 O3. What are the structures of the compounds involved ? 5

(b) Convert
(i) p-MeCOC6H4CO2H—> p-MeCHOHC6H4 COOH
(ii) Ph. H –> 4-NH2 – 2 – OH – benzoic acid.
Answer :

Q. 2. (a) Draw the Fischer projection formulae for :
(i) (R) -3-methyI pentan-l~O|
(ii) (R)-3-methoxy-2-methylpropan-l-0| 2

(b) Predict the product of each of the following reactions :
(i) CH2 = CHCOOH + H2 / Ni -> ?

Image no.7

(c ) Write out the possible isomers of the aromatic compound, C7 H7 Cl. What would each give on oxidation ?
Answer :

Q. 3. Discuss the reaction mechanism of:
(i) Hoesch condensation
(ii) Ester hydrolysis
(iii) Wurtz reaction
Answer :

Q. 4. (a) Write a short note on Keto-enol tautomerism. 2
(b) Starting from diethyl-malonate, how will you prepare the following:
(i) 4-Methylpentanoic acid,
(ii) α-Methylsuccinic acid

(c ) Suggest what A and B could be in the reaction :

Image no.8
Answer :

Q. 5. (a) Discuss the isomerism exhibited by maleic and fumasic acids.

(b) Draw conformational isomers of cyclohexane. Which form is more stable ?

(c ) What happens when :
(i) Glycerol is treated with HI.
(ii) Citric acid is heated with cone. HjSO4.
Answer :

Q. 6- (a) 2,6-Di-t-butylphenol is a much weaker acid than phenol. Explain.

(b) How will you prepare the following :
(i) m-nitroaniline from benzene
(ii) Phenol from aniline. 2

(c ) Discuss the directive influence of-CHO and -NH2 groups in aromatic electrophilic substitution reaction.
Answer :

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Chemistry Paper IV Inorganic Chemistry Previous Year Question Paper Year 2006 : IInd Year

Q. 1. Explain any seven of the following :
(i) Alkali metal salts impart a characteristic color to the flame.
(ii) The solubilities of sulphates of Group II decrease down the group.
(iii) BCI3 is monomeric whereas A1C13 is dimeric.
(iv) PbO2 is less stable than PbO.
(v) HF is a liquid whereas HCl is a gas at room temperature.
(vi) NC13 exists but NC15 does not,
(vii) Lithium carborate decomposes on heating,
(viii) Nitric oxide (NO) is paramagnetic,
(ix) Chlorine is a stronger oxidizing agent than iodine.
Answer :

Q. 2. (a) Why does lithium form normal oxides, sodium forms peroxide and potassium, rubidium form superoxides ? 2

(b) BF3 and BrF3 molecules have different structures. Explain.

(c ) Why oxygen exists as O2 and sulphur as S8 ?
Answer :

Q, 3. (a) Describe roasting. What is auto reduction ? 2
(b) Expain zone refining with diagram. 2
(c ) Explain acidic and basic flux with one example each as used in metallurgy.
Answer :

Q. 4. (a) Give a method for preparing borax from the min¬eral colemanite. Give its Four uses.

(b) Give a method of preparation of diborane. Why it is called an electron deficient compound. Discuss its structure. 3

(c ) Give the reaction of diborane with water and ammonia.
Answer :

Q. 5. Write short notes on any two of the following :
(i) Classification of silicates
(ii) Oxyacids of nitrogen
(iii) Pseudohalogens and pseudohalides.
Answer :

Q. 6. (a) What are interhalogen compounds ? How does VSEPR theory explain the structures of AX3, AX5 and AX7 types?

(b) How is hydrazine prepared by Raschig’s Method ? Give its structure.
Answer :

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Chemistry Paper VI Physical Chemistry Previous Year Question Paper Year 2005 : IInd Year

Q. 1. Answer the following:

(i) How would the energy of an ideal gas change if it is made to expand into vacuum at constant temperature ?

(ii) What is the relation between AH and AE for a reaction involving only condensed phases ?

(iii) Which one of the following properties is an intensive variable:

Internal energy, volume, chemical potential Entropy?

(iv) What is the change in the value of a state function of a system undergoing a cyclic process ?

(v) Under what conditions is ΔG=ΔA?

(vj) Correct the expression : Cp m – Cv m = nR.

(vii) In a reversible process, what is the relationship between internal pressure of a gaseous system and external pressure on it ?
Answer :

Q. 2. (a) Show that for an ideal gas undergoing reversible adiabatic changes

(i) PV y= Constant
(ii) TV y-1= Constant
(b) Calculate W, q, ΔE and ΔH when 2 moles of an ideal gas at 300 K are compressed from 1 atm to 10 atm isothermally and reversibly. What would be the values of the above quantities if the changes were irreversible and carried out against a constant external pressure of 10 atm.
Answer :

Q.3. (a) Derive the relation

Image no.3

Integrate the above equation when Cp values are temperature dependent and ΔCp is given by
ΔC p = Aα + ΔβT + ΔγT2 +…………

(b) The reaction of Cyanamide NH2 CN (S) with oxygen was seen in a bomb calorimeter and ΔE was found to be – 742.7 kj/ mol of NH2 CN (S) at 298 K. Calculate ΔH298 for the reaction

NH2CH(S)+3/2O2(g)—>N2((g) + C02(K) + H20(ℓ)

(c ) If P = f(V,T)show that :

Image no.4
Answer :

Q.4 (a) Explain the term chemical potential and show that :

Image no.5

(b) Show that the decrease in free energy AG is a measure of net useful work under conditions of constant pressure and temperature.

(c ) During a reversible isothermal compression of one of an ideal gas, its pressure increases from 1 atm to 100 atm at a temperature of 27°C. Calculate the entropy change and the free energy change.
Answer :

Q.5. (a) Derive the relation dluKP =AH1

Image no.6

(b) Taking the reaction
so2(g) + ½ O2 (g)=SO3(g)

discuss the effect of an inert gas on the equilibrium.

(c ) The value of K p for the reaction
½ H2(g) + ½ l2(g)=HI(g)

is 8.32 at 600°C and 1 atm pressure. Calculate K p, K c and K x for :-
(i) 2HI(g)=H2(g)=l2(g)
(ii) H2(g) + I2(g)=2HI(g)
Answer :

Q. 6, (a) What do you understand by molal elevation constant of a solvent ? Assuming the clausius-clapeyron equation, derive the expression for the molal elevation constant of a solvent Discuss its
utility.

(b) A solution containing 0.5126 g of naphthalene (M.wt = 128,17) in 50.0 g of carbon tetrachloride yields a boiling point elevation of 0.402°C, while a solution of 0.6126 g of an unknown solute in the same weight of solvent gives a boiling point elevation of 0.647°C. Find the molecular weight of the unknown solute.
Answer :

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Chemistry Paper V Organic Chemistry Previous Year Question Paper Year 2005 : IInd Year

Q.I. (a) A and Bare two isomeric dicarboxylic acids whose molecular formula is C4 H4 O4. A adds 1 mole of bromine to give a product from which a pair of enantiomorphs may be resolved. B adds 1 mole of bromine to yield a compound which is not resolvable. Suggest structural formulae for A and B and the two dibromo compounds. 4

(b) Draw all possible stereoisomers for the following and state which are optically active, inactive forms:
(i) MeCHOHCHOHMe
(ii) MeCHClCO2H
Answer :

Q.2. (a) Arrange the following in order of increasing b.p. and give your reasons:
(CH2OH)2, (CH2OMe)2, HOCH2CH2OMe

(b) What are the effects of the following groups on the basicity of aniline when in p-position:
(i) -NO2
(ii) -OCH3
(iii) -N(CH3)2

(c ) o-Nitrophenol has a lower b.p. and lower water solubility than the pisomer. Explain.

(d) The sodium salt of sulphanilic acid can be readily acetylated with AC2O, but not the free acid. Explain.
Answer :

Q.3. (a) Give the E-Z designation to the following compounds:

Image no.1

(b) How would you use:
(i) Acetoacetic ester synthesis to prepare 2-pentanone ?
(ii) Malonic ester synthesis to get hexanoic acid ? 2

(c ) What happens when glycerol is reacted with :
(i) HIO4
(ii) KHSO4.
Answer :

Q. 4. (a) How will you prepare the following:
(i) p-Bromotoluene from ptoluidine;
(ii) p-Dinitrobenzene from pnitroaniline;
(iii) Phenol from cumene;
(iv) Picric acid from chlorobenzene. 4

(b) Coupling of benzene diazonium chloride takes place either under mild alkaline or mild acidic conditions. Explain by taking a suitable example.
Answer :

Q. 5. (a) Write short notes on the following:
(i) Tautomerism;
(ii) Fischer projection formula;
(iii) Cannizzaro’s reaction.
Answer :

Q. 6. (a) What is the action of heat on α-β-and hydroxy acids ?

(b) Chlorobenzene is less reactive than benzyl chloride towards nucleophiles. Explain.

(c ) Image no.2
Answer :

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Chemistry Paper IV Inorganic Chemistry Previous Year Question Paper Year 2005 : IInd Year

Q.I. Explain any seven of the following:
(i) Chlorine is a stronger oxidizing agent than Iodine.
(ii) PC1S exists but PH5 does not.
(iii) CO2 is a gas while SiO2 is a high melting solid.
(iv) Graphite is a lubricant and a good conductor of
(v) The solubility of group II sulphates decreases as we go down the group.
(vi) Alkali metals are photoconductors.
(vii) Nitric oxide (NO) is paramagnetic.
(viii) NF3 is extremely stable whereas NC13 is easily hydrolysed.
(ix) Sn (II) is a strong reducing agent.
Answer :

Q.2. (a) What is roasting? Give examples of ores which are roasted. What is Autoreduction ?
(b) Give the Mond’s process for Nickel extraction and purification.
Answer :

Q. 3. (a) Draw a neat diagram and explain zone refining. 3
(b) How is sulphur dioxide prepared ? Illustrate with one example each, its oxidizing and reducing character. Discuss its structure.
Answer :

Q. 4. Describe the preparation, properties and structure of Borazine. Why is it called inorganic benzene ?
Answer :

Q. 5. (a) What are interhalogen compounds? How are they different from the parent halogens ?

(b) Give the structure of AX3, AX5 and AX7 types of compounds as explained by the VSEPR Theory.
Answer :

Q.6. (a) Discuss the nomenclature of oxyacids of phosphorous. Draw the structures of four such acids.

(b) Draw the structures of the oxyacids of Chlorine and explain their relative acidic character.
Answer :

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