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ENGINEERING CHEMISTRY-IIQUESTION BANK

UNIT I

ELECTROCHEMISTRY

PART-A

1.State single electrode potential

2.State standard electrode potential

3.What is reference electrode

4.Define electrode potential

5.what is an ion selective electrode

6.How is Ph of a solution determined using glass electrode

7.Mention the significance of emf series.

8.How will you predict the spontanenity of a redox system using emf

9.What is redox titration give example.

10.Define emf .

11.List the factors affecting emf of a cell

12.Mention the advantages of conductometric titration

13.Write the limitations of hydrogen electrode

14.Write the conditions for an electrochemical cell to act as an standard cell

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15.Mention the advantages of potentiometric titration

PART-B

1.Derive Nernst equation and mention its significance

2.Define emf. How can it be measured potentiometrically

3.What are reference electrode.Describe calomel electrode with a neat diagram

4.Explain the conductometric titration of strong acid by strong base

5.Explain the principle involved in potentiometric titration.Write an experimental procedure for carrying out the titration of redox reaction.

6.Explain the measurement of PH of a solution using glass electrode

7.Difference between reversible and irreversible cell

8.What is irreversible cell explain the irreversibility taking a suitable example

9.Describe the importance of electrode potential

10.Ion-selective electrode explain its principle and working

11.Difference between electrolytic and electrochemical cell

12.What is the concentration of Ni2+ in the cell at 25°c,if the emf of the cell is 0.601 v?

Ni (s)/ Ni2+(C=?)//Cu2+(0.75)/Cu(s)

Given. E°= Ni (s)/ Ni2+=0.25v, E°= Cu2+/Cu(s)=0.34 v

13.Calculate the emf of the cell Zn/Zn 2+ (0.1M) //Ag+ (0.1M)/Ag ;E°cell=1.56 v

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14.Consider the cell reaction

Zn(s)+Fe2+(0.005M)↔Zn2+(0.01M) +Fe(s)

Given that the standard emf of the cell at 298K is 0.323 v i)construct the cell ii)calculate emf of the cell

UNIT II CORROSION AND ITS CONTROL

PART –A

1.Define corrosion

2.State pilling bedworth rule

3.What is differential aeration

4.Explain galvanic corrosion with example

5.What is meant by pitting corrosion

6.Name the factors influencing corrosion

7.Write the effect of pH of conducting medium on corrosion of metals.

8.How does magnesium corrode faster than iron

9.Mention the principle involved in impressed cathodic current protection method of prevention of

corrosion.

10.Zinc is more readily corrode when coupled with copper than with lead. Why?

11.What is inhibitors and mention their types.

12.What is the role of pigment in paint? Give two examples.

13.What is the functions of driers in the paint?

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14.What are the objectives of electroplating on non-metals

15.What is electroless plating

16.How is Ni plating done by electroless plating?

PART-B

1.Mechanism of chemical corrosion and also explain the nature of oxide film formed over the metal

2.Mechanism of electrochemical corrosion

3.Briefly explain about differential aeration corrosion

4.Explain inhibition of corrosion by sacrificial anodic protection and impressed cathodic current protection method 5.Explain the factors influencing the rate of corrosion

6.What are inhibitors? How are they classified with suitable example

7.Discuss the mechanism of drying of oil paint.

8.State the constituents of oil paints with examples and their functions.

9.What are the main objectives of electroplating .Give an account of the method used in electroplating of gold.

10.What is electroless plating? Write short note on electroless nickel plating and discuss its application

11.Difference between electroplating and electroless plating

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UNIT III- FUELS AND COMBUSTION

PART –A

1.What is metamorphism or coalification of coal?

2.Difference between proximate and ultimate analysis

3.What is metallurgical coke?

4.Mention the characteristics of metallurgical coke.

5.How coke is superior to coal?

6.What is drawback of presence of Sulphur in the coal?

7.What is meant by refining of petroleum?

8.What is cottrell’s process in crude oil refining.

9.Define cracking. What is the necessity of cracking?

10.Difference between the thermal and catalytic cracking.

11.What is meant by hydrogenation of coal?

12.Define the term knocking. 13.How will you improve the anti-knocking characteristics of diesel

14.Define octane number. How it can be improved?

15.Define cetane number. How it can be improved?

16.What is leaded petrol. Give its significance in automobiles.

17.What is producer gas and water gas

18.Give the composition and uses of producer gas

19.Give the composition and uses of water gas

20.What is CNG? Mention it primary components.

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21.Define calorific value of a fuel

22.Define GCV and LCV of a fuel.

23.Give the Dulong’s formula for the calculation of GCV and NCV

24.Mention the uses of flue gas analysis

PART-B

1.Explain the proximate analysis of coals? Write its significance

2.Write brief note on ultimate analysis of coal

3.How is metallurgical coke manufactured by Otto-Hoffman oven

4.What is meant by crude petroleum? Discuss the principle steps in the refining of crude petroleum

5.Explain the fixed bed catalytic cracking for the manufacture of gasoline

6.Explain the moving bed catalytic cracking for the manufacture of gasoline.

7.Describe the manufacture of gasoline by Fisher-Tropsch method.

8.How will you obtain synthetic petrol by Bergius process

9.What is water gas?How it is manufactured? Give the chemical reaction taking place in different

zones

10.How is producer gas manufactured? state its composition and uses?

11.What are LPG and CNG? Discuss the advantages of LPG over gaseous fuel and CNG over LPG 12.Explain the causes, mechanism and prevention of knocking of petrol in I.C. engine

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13.List out the difference between petrol and diesel as I.C. engine fuels

14.With a neat diagram explain the analysis of flue gas by Orsat apparatus and mention the

precautions to be followed during the analysis.

15. A sample of coal was found to contain the following, C=81%,H=4%,O=2%,N=10%,S=2% and the

remaining being ash. Estimate the quantity of minimum air required for the complete combustion of 3

kg of the sample.

16.The percentage composition by volume of a producer gas is

CH4=3.6%,CO=25%,H2=10%,CO2=10.8%N2=50.7%.Calculate the theoretical quantity of air required per m3 of the gas.

17.Calculate the volume of air required for complete combustion of 100 m3of a gaseous fuel having the following analysis composition by volume H2=50%,CH4=36%,N2=1.5%,CO=6%,C2H4=4%,CO2=2.5%

18.A gaseous fuel has the following composition by volume H2=12%,CH4=2%,CO=24%,CO2=5%O2=2%

and the rest N2.Calculate the volume of air needed for the complete combustion of 100 m3of the fuel.

19.A sample of coal was found to have the following percentage composition.

C=75%,H2=5.2%,O2=12.8%,S=1.2% and the rest ash. Calculate the amount of air needed for the complete combustion, if 1 kg of the coal is burnt with 30% excess air.

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20.Calculate the volume of air required for the complete combustion of 1 m of the gaseous fuel having

the following composition by volume H2=50%,CH4=36%,N2=1.5%,CO=6%,C2H4=4%, H2O vapour=2.5.

UNIT IV - PHASE RULE

PART-A

1.State phase rule.

2.Define phase with example

3.Define component with example

4.What is meant by degree of freedom?

5.What is phase diagram? Mention its types.

6.Write the uses of phase diagram

7.What is meant by metastable equilibrium

8.State reduced phase rule

9.Mention the uses of cooling curves

10.What is eutectic point

11.Differentiate melting point, eutectic point and triple point

12.What is pattinson’s process?

13.Mention the uses of eutectic system

14.Mention the merits of phase rule

15.Explain the limitation of phase rule

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16.How many phases,components are existing at triple point in ice-water-water vapour system

17.Calculate the number of phases present in the following system

a)NH4 Cl(s)↔NH3(g) + HCl(g)

b)An emulsion of oil in water

c) MgCO3(s)↔ MgO(s) +CO2

d)Ice(s)↔Water(l)↔water vapours(g)

18.Calculate the number of phases and components present in following system

CuSO4(s)+5H2O(l)↔ CuSO4.5H2O(s)

PART-B

1.State phase rule and explain the terms involved in it

2.Draw a neat phase diagram of water system and explain the curves,areas and points in it

3. Draw a neat phase diagram and explain the lead-silver system briefly write about pattinsons’s process

4.What is thermal analysis. Draw the cooling curves of a pure substance and a mixture and discuss

5.What are the merits and demerits of phase rule

6.How is silver separated from argentiferous lead? Explain with the help of phase diagram?

7.What is metastable equilibrium? Explain this state in water system.

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ALLOYS

PART-A

1.Define alloy

2.Mention the properties of alloys

3.Give any two uses of brass and bronze

4.Mention any five purpose of making alloys

5.Give composition and uses of nichrome

6.What is heat treatment of alloys

7.What are the objectives of heat treatment

8.Define the terms Annealing ,Hardening, Tempering, Normalising

9.What is alnico

10.Give the percentage composition of bronze

11.Give any two uses of brass and bronze

PART-B

1.What are the main purpose of alloying steel.

2.Write note on heat treatment of steel

3.What are alloys? Write the chemical composition and uses of Heat treatable stainless steel and non heat treatable stainless steel

4.Discuss the composition, characteristics and uses of non ferrous alloy such as bronze.

5.Mention the composition,properties and uses of nichrome

6.How are the properties of metals improved by alloy formation.

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UNIT-V ANALYTICAL TECHNIQUES

PART-A

1.State Lambertz law

2.State Beer-Lambertz law

3.What is colorimeter.

4.A solution of thickness 2 cm transmits 40% incident light.Calculate the concentration of the solution given that ε=6000 dm3 mol-1 cm-1

5.What is principle involved in flame photometry.

6.IR spectra us often characterized as molecular finger prints.justify

7.What are chromphore? give example

8.What are auxochrome? give example

9.Define the bathochromic shift 10.What are the various type of electronic transition taking place in UV spectroscopy

11.What is finger print region and mention its uses.

12.Calculate the number of IR bands (mode of vibrations)for CH4,C2H6,C6H6,H2O,CO2

13.Write the basic principle of atomic absorption spectroscopy.

14.Mention the application of AAS

15.What are the source of IR radiation in IR spectrophotometer

16.Difference between flame photometery and AAS

17.Write the application of IR spectroscopy

18.Mention the limitation of flame photometry.

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PART-B

1.Derive Beer-Lambert’s law and write all the limitations observed in the quantitative analysis

2.Explain briefly colorimetry with neat diagram

3.Explain briefly the principle and instrumentation of flame photometry

4.Mention the applications of UV spectroscopy

5.What is IR spectroscopy?Explain the different region of IR.

6.What is the principle of flame photometry?How do you estimate sodium using flame photometry?

7.Explain the main features of working of UV-visible spectrometer with a neat block diagram.

8.Give a neat sketch of atomic absorption spectrometer and explain the components.

9.Explain the estimation of nickel by AAS

10.Explain the principle, instrumentation and application of IR spectroscopy

11.Explain the electronic transition caused by energy absorbed in the UV region

12.Give the possible stretching and bending vibrations of the following CO2,H2O,-CH2