PERI INSTITUTE OF TECHNOLOGY ENGINEERING CHEMISTRY – I ...
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PERI INSTITUTE OF TECHNOLOGY
ENGINEERING CHEMISTRY – I
SUBJECT CODE: 183101 [COMMON FOR ALL BRANCHES]
(2011 -12)
2 MARKS QUESTIONS & ANSWERS
WITH PART B
DEPARTMENT OF CHEMISTRY
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ENGINEERING CHEMISTRY – 183101 AIM To impart a sound knowledge on the principles of chemistry involving the different application oriented topics required for all engineering branches.
OBJECTIVES • The student should be conversant with the principles water characterization and treatment of potable and industrial purposes. • Principles of polymer chemistry and engineering applications of polymers • Industrial applications of surface chemistry • Conventional and non-conventional energy sources and energy storage devices and Chemistry of engineering materials
UNIT I WATER TECHNOLOGY [9] Characteristics – alkalinity – types of alkalinity and determination – hardness –types and estimation by EDTA method (problems); Domestic water treatment –disinfection methods (Chlorination, ozonation. UV treatment) – Boiler feed water– requirements – disadvantages of using hard water in boilers – internal conditioning (phosphate, calgon and carbonate conditioning methods) – external Conditioning – demineralization process – desalination and reverse osmosis.
UNIT II POLYMERS AND COMPOSITES [9] Polymers-definition – polymerization – types – addition and condensation polymerization – free radical polymerization mechanism – Plastics, classification – preparation, properties and uses of PVC, Teflon, polycarbonate, polyurethane,nylon-6,6, PET- Rubber -vulcanization of rubber, synthetic rubbers – buty1 rubber, SBR, Composites – definition, types polymer matrix composites – FRPonly.
UNIT III SURFACE CHEMISTRY [9] Adsorption – types – adsorption of gases on solids – adsorption isotherms –Frendlich and Langmuir isotherms – adsorption of solutes from solution – role of adsorbents in catalysis, ion-exchange adsorption and pollution abatement.
UNIT IV NON-CONVENTIONAL ENERGY SOURCES AND STORAGE DEVICES [9] Nuclear energy – fission and fusion reactions and light water nuclear reactor forPower generation (block diagram only) – breeder reactor – solar energy
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conversion – solar cells – wind energy – fuel cells – hydrogen – oxygen fuel cell –batteries – alkaline batteries – lead–acid, nickel–cadmium and lithium batteries.
UNIT V ENGINEERING MATERIALS [9] Refractories – classification – acidic, basic and neutral refractories – properties(refractoriness, refractoriness under load, dimensional stability, porosity, thermalspalling) – manufacture of alumina, magnesite and zirconia bricks, Abrasives –natural and synthetic abrasives – quartz, corundum, emery, garnet, diamond,silicon carbide and boron carbide. Lubricants – mechanism of lubrication, liquidlubricants, - properties – viscosity index, flash and fire points, cloud and pourpoints, oilyness) – solid lubricants – graphite and molybdenum sulphide.Nanomaterials – introduction to nanochemistry – carbon nanotubes and their Applications
TOTAL: 45 PERIODS
TEXT BOOKS: 1. P.C.Jain and Monica Jain, “Engineering Chemistry” Dhanpat Rai Pub, Co., New Delhi (2002). 2. S.S. Dara “A text book of engineering chemistry” S.Chand & Co.Ltd., New Delhi (2006). REFERENCES: 1. B.K.Sharma “Engineering chemistry” Krishna Prakasan Media (P) Ltd., Meerut (2001). 2. B. Sivasankar “Engineering Chemistry” Tate McGraw-Hill Pub.Co.Ltd, New Delhi (2008).
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TOPICS COVERED
UNIT - I WATER TECHNOLOGY
UNIT - II POLYMERS AND COMPOSITES
UNIT - III SURFACE CHEMISTRY
UNIT - IV NON-CONVENTIONAL ENERGY SOURCES
AND STORAGE DEVICES
UNIT- V ENGINEERING MATERIALS
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UNIT - I Water Technology
1. Define hard water and soft water.
Water which does not produce lather with soap solution but forms a white
precipitate is called hard water. Water which lathers easily with soap solution is called
soft water.
2. Give a chemical test to detect hardness of water.
Hardness can be detected by treating water with soap, as hard water forms a white
precipitate with soap solution.
3. What is aeration? Why is it required?
Aeration is a process in which water is mixed with air.
The main purpose of aeration is-
1. To remove CO2, H2O and other volatile substance causing bad taste and odour.
2. To remove impurities like Fe and Mn as their respective hydroxide.
4. Distinguish between priming and foaming.
Priming is the process of production of wet steam during the process of steam
production in boilers. During steam production certain water droplets also get into steam
due to some dissolved solids in water, high steam velocity or irregular steam velocity.
Foaming is the production of persistent bubbles in the water which do not break easily due
presence of oily or soapy substances.
5. What are boiler compounds? Give examples.
The chemicals added inside the boilers (during internal treatment of water) to
remove scale forming substance are called boiler compounds.
Eg. Sodium phosohate, calgon.
6. What is calgon? What is its role in water treatment?
It is chemical added inside the boilers during internal treatment of water. Calgon is
sodium hexametaphosphate. (NaPO3)6 or Na2[Na4(PO3)6
It forms a highly soluble complex with Ca2+
ions of hard water and prevents the formation
of scale in boilers.
7. What is desalination? Name few methods of converting sea water into fresh
water?
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The process of removal of extra common salt from sea water is described as
desalination or desalting.
The various desalination processes
1. distillation
2. freezing
3. reverse osmosis
4. electro dialysis
8. What is meant by break point chlorination?
Chlorination of highly polluted water such that after all the bacteria are killed, the
organic impurities present in water are completely oxidized and the residual chlorine in
water is about 0.1 ppm is called break point chlorination.
9. Define Temporary and permanent Hardness.
The hardness removed by boiling the water is called as temporary hardness and it is
due to the presence of carbonate and bicarbonate of calcium and magnesium.
The hardness due to the presence of sulphate and chlorides of calcium and Magnesium is
called as permanent Hardness.
10. Name any two disadvantages of using hard water for domestic purpose.
1. Hard water when used for drinking affects our digestive system and also leads to the
formation of stones in kidney.
2. Hard water when used for washing does not lather with soap easily and thereby
causing wastage of soap.
11. Discuss ozone gas treatment.
Ozone is an unstable allotrope of oxygen. It is a powerful disinfectant. Ozone is
readily absorbed by water. Ozone contains three oxygen atoms and one atom breaks easily.
This produces nascent oxygen [O] which is a powerful disinfectant. It kills all bacteria and
does not produce any odour or taste.
12. Explain ultraviolet treatment.
Ultraviolet rays are powerful disinfectant. They are produced by passing electric
current through mercury vapour lamp. When water is allowed to flow in thin stream. UV
rays from the lamp destroys pathogens completely.
13. Define nuclear fission reaction.
It is defined as the process of splitting of heavier nucleus into two or more smaller
nuclei by bombarding with slow speed neutrons with simultaneous liberation of large
amount energy.
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14. What are batteries? Mention the basis for their functioning.
`Batteries may be considered as store houses for electrical energy on demand. The
basis for battery technology is that the chemical energy derived from the chemical reactions
in the battery is converted into electrical energy.
15. Explain alkaline battery.
This is an improved form of dry cell. Here,
Anode: Zinc, Cathode: MnO2, Electrolyte: KOH
This cell drives power from the reduction of MnO2 cathode and the oxidation of Zn
anode. The emf of the cell is 1.5V. It is used in calculators, watches etc.
16. What is a storage cell?
A storage cell is the one which can operate both as a voltaic cell and as an
electrolytic cell. When it acts as a voltaic cell, it supplies electrical energy and becomes run
down. When it is recharged, the cell operates as an electrolytic cell.
17. Write few applications of solar cells. a. Solar cells are used in boilers to produce hot water for domestic and industrial
uses.
b. Solar cells can be used for lighting purposes.
c. Solar cells can be used to drive vehicles.
d. They can be used to produce H2 by electrolysis of water.
18. A sample of water contains 120mgs of MgSO4 per litre. Calculate hardness in
terms of CaCO3 equivalents.
Given : The amount of MgSO4 = 120 mgs/lit.
Amount equivalent to = The amount of hardness producing salt x 100
CaCO3 Molecular weight of hardness producing salt
We know that, the molecular weight of MgSO4 = 120
Therefore, amount equivalent to CaCO3 = 120 x100
120
= 100 mgs/lit.
19. Write the uses of Lead Storage battery. (i) It is used in the automobiles.
(ii) It is used in gas engine ignition, telephone exchanges,
Hospitals, power stations.
20 . What is meant by boiler corrosion? How is it prevented? Boiler corrosion is due to the presence of dissolved gases such as O2 CO2 and easily
hydrolysable salts t like MgCl2.
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Mechanical deaeration is a method used to remove dissolved gases such as O2 and
CO2. The principles involved in this process are the solubility of a gas is directly
proportional to pressure and inversely proportional to temperature.
21. What are the requisites of drinking and boiler feed water? (Nov 2001)
Boiler water must be free from hardness causing substances, dissolved gases, oil,
silica. Water should be clean, colourless and odourless. It should be free from
pathogenic organisms. It should not be excessively hard or soft.
22.What is a primary battery? Give an example (June 2006)
(Or) What are primary cells?
In primary cells, the electrode and the electrode reactions cannot be reversed by
passing an external electrical energy. The rections occur only once and after use they
become dead. Therefore, they are not chargeable. Eg Dry cells.
23. How are anodic and cathodic electroactive materials made in Ni-Cd battery?
Nickel-cadmium cell consists of a cadmium anode and a metal grid containing a
paste of NiO2 acting as a cathode. The electrolyte in this cell is KOH.
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UNIT -II POLYMER AND COMPOSITES
1. What is heterochain polymer ? Give one example.
If the main chain of a polymer ( backbone) is made up of different atoms, it is called
heterochain polymer.
Eg. Nylon, terylene.
2. Mention few advantages of plastics.
a.They are light in weight.
b.They are low melting point.
c.They can be easily moulded.
d.They have high resistance to abrasion.
e.They are not affected by insects
f. They are corrosion resistant
3. What are disadvantages of plastics? a. High cost
b.Combustibility
c.Softness
d.Poor ductility
e.Low heat resistance.
4 .Differenitate between thermoplastics and thermosetting plastics
S. No. Thermoplastics
Thermosetting plastics
1 They are formed by addition
polymerization.
They are formed by
condensation polymerization
2 They consist of linear, long
chains.
They consist of three
dimensional net work structure.
3 They are weak, soft and less
brittle.
They are strong, hard and more
brittle.
4 They soften on heating and
harden on cooling.
They do not soften on heating.
5 They can be remolded. They cannot be remoulded.
6 They are soluble in many organic
solvents
They are in soluble in all organic
solvents
5. What are plastics? How does it differ from a resin?
Plastics are high molecular weight organic materials, which can be moulded into any
desired shape by the application of heat and pressure in presence of catalyst. Actually a
plastic is made by compounding the virgin polymer with a lot of additives.
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Resins are the basic binding materials. They are the major part of the plastics.
Thermoplasts do not undergo crooslinking during molding operation. Thermosetting
resins actually undergo crooslinking during molding operation.
6. Mention the uses of PVC
a. It is the most widely used synthetic plastic both in unplasticised and plasticised
form.
b. It is used for the production of pipes, cable insulation equipment parts, raincoats etc.
c. PVC in the form of sheets find use as tank linings light fittings, trays, motor cycle
mudguards.
7 .Write few uses of Teflon.
1) Its electrical application include wire and cable insulator, insulation for motors,
generators.
2) It is used in non-lubricated bearings, lining for trays in bakeries etc.
3) It is used for making non-sticking stopcocks for burettes and kitchen appliances.
8. Define the term functionality of a monomer. Give its significance.
The number of reactive sites or bonding sites or polymerisable groups present in a
monomer is known as its functionality.
Eg. Ethylene, CH2=CH2 is bifunctional; double bond provide two reactive sites.
9. What is copolymerization ? How copolymerization is superior to homo
polymerization?
Copolymerisation is the joint polymerization of two or more different type of
monomeric units.
Copolymerization provides a specific property to a polymer. It controls various polymer
properties like hardness rigidity, heat resistance and crystallinity. Hence, it is superior to
homopolymerisation.
10. How is vinyl chloride prepared?
1) By the reaction of hydrogen chloride with acetylene in the presence of
catalyst.
CH = CH + HCl → CH2 = CHCl
2) By the dedehydrochlorination of ethylene dichloride in
vapour phase.
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CH2Cl – CH2Cl → CH2 = CHCl + HCl
11. What are polymer alloy and polymer blend? Polymer blend is a simple physical combination of two or more incompatible polymers.
But polymers alloy is a compatible mixture of two or more polymers, which interact
chemically in the presence of compatibilisers under pressure, temperature.
12.Write a note on epoxy resin
It is manufactured from epichlorohydrin and bisphenol – A. It can be used in solid or
liquid form. They stick to a number of materials including metals and glasses. Their trade
name is araldite.
13. State the monomers required for synthesizing SBR?
Styrene and butadiene
14. State the monomers required for synthesizing butyl rubber?
Isobutylene and isoperene
15. State the monomers required for the manufacture of Nylon 6,6?
Adipic acid and hexamethylene diamine
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UNIT –III
SURFACE CHEMISTRY
1. Define adsorption.
The phenomenon of higher concentration of any molecular species at the surface
than in the bulk of a solid is known as adsorption.
2. Distinguish between Adsorption, Absorption and Sorption.
The Phenomenon of concentration of molecules of a gas or liquid at a solid surface called
as adsorption. Eg. Adsorption of gases like O2, Cl2, NH3 on charcoal.
The Phenomenon of distribution of molecules of a gas or liquid through out the body of
the solid or liquid medium called as absorption
Eg., Chalk dipped on ink adsorbs ink and sponge absorbs water.
If both adsorption and absorption takes place simultaneously it is called as sorption.
Adsorption Absorption Sorption
3.What is chemisorption?
If the adsorbed materials are held on the surface of the adsorbent by chemical bonds, it is
called chemisorption or activated adsorption.
Eg., adsorption of H2 on Ni.
4. Define Physisorption? Give examples
The process in which the adsorbed molecules held on the surface of the adsorbednt by
physical or weak vanderwaal’s forces of attraction is called as Physisorption.
Eg., Adsorption of H2 or O2 on Charcoal.
5.Which type of Adsorption is Reversible in nature? Why?
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Chemisorption is irreversible in nature as it forms surface compounds during
adsorption. But physisorption is not reversible.It doesn’t form any compounds and
desorption is so easier.
6.What is meant by adsorption isotherm?
A mathematical expression or graphical curve which represents the relation
between the amounts of gas adsorbed by the adsorbent and the equilibrium pressure is
called the adsorption isotherm.
7.What is Freundlich adsorption isotherm?
Freundlich gave an empirical relationship between the quantity of gas adsorbed by
a given amount of solid adsorbent surface and pressure at a particular temperature. It
states that
X = k p n
M
where, x is the weight of gas adsorbed by m grams of the adsorbent at a pressure, p.
k and n are constants at a particular temperature and for a particular adsorbent and gas.
8.Discuss langmuir adsorption isotherm.
Irving langmuir gave an empirical relationship between the amount of gas
adsorbed to the pressure of the gas at constant temperature. It can be mathematically
represented as,
KP
X = k’’ ---------
1+ KP
At low pressure, X = kp1
At high pressure X = kP°
At intermediate pressure it becomes, X = kpn and the value n lies between 0 and 1.
9 .Distinguish between chemisorption and Physisorption (or) How does
chemisorption differ from physisorption
S.No. PHYSISORPTION CHEMISORPTION
1. Does not show any specificity. Its highly specific
2. It occurs at low temperature It occurs at higher temperature.
3. It is reversible in nature. It is irreversible in nature.
4. It is multiplayer phenomenon. It occurs only in the upper layer.
5. Heat of adsorption is 30 KJ mol-1
. Heat of adsorption is 80KJ mol-1
.
6. It is caused by weak, inter
molecular vanderwaals forces.
It is caused by chemical bond
formation.
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10. What are promoters? Promoters are defined as “the substances which increase the activity of a catalyst”.
11. What is catalytic poisoning? Catalytic poison is defined as a “a substance which destroys the activity of the
catalyst to accelerate a reaction.’ This process is called catalytic poisoning.
12. What is chromatography? Chromatography may be defined as, “an analytical technique for identification and
separation of various components of a mixture on the basis of difference in their affinity
for stationary and mobile phases”.
13. What is the effect of temperature and pressure on the adsorption of hydrogen gas
on charcoal?
Adsorption of H2 on charcoal is rapid at lower temperature and decrease with
increase in temperature, but the rate of adsorption increases with the increase of pressure.
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UNIT IV NON CONVENTIONAL ENERGY SOURCES AND STORAGE DEVICES
1. What is nuclear chain reaction? A fission reaction where the neutrons from the previous step continue to propogate and
repeat the reaction is called nuclear chain reaction.
2. What is nuclear energy? The energy released by the nuclear fission is called nuclear fission energy (or) nuclear
energy.
3. What is light water nuclear – power plant? Light-water nuclear power plant is the one, in which U
235 fuel rods are submerged in
water. Here the water acts as a coolant as well as a moderator.
4. What is super critical mass and sub-critical mass of U235
? Super critical mass
If the mass of the fissionable material (U235
) is more than the critical mass, it is called
super critical mass.
Sub-critical mass
If the mass of the fissionable material is smaller than the critical mass, it is called
Sub-critical mass.
5. What is fissile nucleides and fertile nucleides? The fissionable nucleides such as U
235 & Pu
239 are called fissile Nucleides.
The non-fissionable nucleides such as U238
& Th232
are called fertile nucleides.
6. What is thermal conversion? Thermal conversion involves absorption of thermal energy in the form of IR radiation.
Solar energy is an important source for low-temperature heat (temperature below 100.C),
which is useful for heating buildings, water and refrigeration.
7. What are the applications of H2-O2 fuel cell?
(a) H2-O2 fuel cells are used as auxiliary energy source in space vehicles,
submarines or other military-vehicles.
(b) In case of H2-O2 fuel cells, the product of water is proved to be a valuable
source of fresh water by the astronauts.
8. What are the advantages of alkaline battery over dry battery? (i) Zinc does not dissolve readily in a basic medium.
(ii) The life of alkaline battery is longer than the dry battery, because there is no
corrosion on Zn.
(i) Alkaline battery maintains its voltage, as the current is drawn from it.
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9. How is NICAD battery constructed? Nickel cadmium cell consists of a cadmium anode and a metal grid containing a
paste of NiO2 acting as a cathode. The electrolyte in this cell is KOH.
10. Describe Lithium battery. The lithium battery consists of a lithium anode and a TiS2 cathode. A solid electrolyte,
generally a polymer, is packed in between the electrodes. The electrolyte(polymer)
permits the passage of ions but not that of electrons.
11. What are the important requirement of a battery? A useful battery should fulfil the following requirements.
(i) It should be light and compact for easy transport.
(ii) It should have long life both when it is being used and when it is not
used.
(iii) The voltage of the battery should not vary appreciably during its use.
12.Write the uses of lead storage battery. i) Lead storage cell is used to supply current mainly in automobiles such as cars, buses,
trucks etc.
ii)It is also used in gas engine ignition, telephone exchanges, hospitals, power station etc.
iii) It is used for SLI system (Starting Lighting-Ignition) of road automobiles.
16. What is a fuel cell or flow battery? A fuel cell is a device in which thermal energy is directly converted to electrical
energy. In a conventional system, thermal energy is converted to mechanical energy and
the mechanical energy into electrical energy.
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UNIT – V
ENGINEERING MATERIALS
1. What are abrasives?
Abrasives are the hard substances used for grinding, cutting, sharpening, polishing or
drilling purposes. They are used in the form of granules or powder. They are characterized
by high hardness, high melting point and chemical inertness.
2. What is abrasive power? It is the strength of an abrasive to grind away other materials. It depends on
hardness, toughness and refractoriness.
3. How is carborundum manufactured?
It is manufactured using a mixture containing sand (54%) , coke (34%) saw dust
(10%) and common salt (2%). The mixture is heated in an electric furnace at 2000ºC for 36
hours.
SiO2 + 3C → SiC +2CO
4. What are refractories ? Refractories are any inorganic materials which can withstand high temperature
without softening, melting or deformation in shape.
5. What are the functions of lubricant ? 1) It reduces surface deformation, wear and tear.
2) It reduces loss of energy in the form of heat.
3) It reduces the maintenance and running cost of the machine.
4) It prevents the entry of moisture, dust and dirt between the
moving parts.
5) It acts a coolant.
6. Define the terms flash point and fire point .
Flash point: It is the lowest temperature at which the oil gives off enough vapours that will
flash if a small flame is brought near to it.
Fire point: Its is the lowest temperature at which the oil gives off enough vapours that must
burn continuously for at least 5 seconds when a small flame is brought near to it.
7. Define the terms lubricant and lubrication. Lubricant is a substance used to reduce the friction between two moving surface.
The process of reducing friction between two moving surfaces with respect to one another
by introducing lubricant to them is called lubrication.
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8. Name the stages in the manufacture of refractory. 1) Crushing
2) Grinding
3) Screening
4) Mixing
5) Moulding
6) Drying
7) Firing
9. Mention the various physical and chemical factors affecting adhesive action.
Physical factors: surface tension, porosity, smoothness, viscosity, time etc.
Chemical factors: polar groups, degree of polymerization, chain length , PH etc.,
10.Write a note on epoxy resin.
It is manufactured from epichlorohydrin and bisphenol – A. It can be used in solid or
liquid form. They stick to a number of materials including metals and glasses. Their
trade name is araldite.
11. What is hardness of an abrasive? It is ability of an abrasive to grind or scratch away other materials. The harder the
abrasive quicker will be its abrading action.
12. Define an Adhesive. Give the classification. Substances capable of holding materials together by surface attachment are called
adhesives.
Natural adhesive: Shellac resins, starch adhesives
Synthetic adhesive: Epoxide resin, silicone resin.
13. What are adhesive and adherent? Substances capable of holding materials together by surface attachment are called
adhesives. The materials held together by an adhesive are called adherents.
14. Define Viscosity index.
Viscosity index is defined as the average decrease in viscosity of an oil per degree
rise in temperature between 100º F and 210º F.
15. What are viscosity index improvers ? Give examples. Viscosity index improvers are substances, added to prevent the Oil from thinning at
higher temperature and thickening at lower temperatures.
16. What are advantage and disadvantage of Adhesive? Advantages:
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(i) Adhesives can be applied to the surfaces of any material.
(ii) Surfaces are rapidly and easily attached to each other.
(iii) Adhesive bondings require less after finishing when compared to other
joining process like welding, soldering etc.
(iv) No high heat is required for bonding.
17. What are Nano materials ? Nano materials are the materials having components with size less than 100nm
atleast in one dimension.
18. What are Carbon Nano tubes? They are allotropes of Carbon with a nanostructure having a length – to – diameter ratio
greater than 1,000,000. When graphite sheets are rolled into a cylinder their edges joined
and form carbon nanotubes i.e., carbon nanotubes are extended tubes of rolled graphite
sheets.
19.How are carbon nanotubes classified? Carbon nanotubes are classified into two types as
a. Single-walled nanotubes (SWNTs)
b. Multi – walled nanotubes (MWNTs).
20.Mention the important forms of SWNTs. SWNTs consist of one tube of graphite. It is one-atom thick having a diameter of
2nm and a length of 100µ m. It forms the following three type of structures.
Arm structure, Zig-zag & Chiral structure..
21. Name some important methods of manufacture of CNTs. Carbon nanotubes can be made by any one of the following methods.
Pyrolysis, Carbon arc methods, Laser evaporation, Chemical vapour deposition.
22. How are CNTs used in the fuel cell? SWNT is used in the form of plate or paper as anode in the fuel cell.
23. What is the main requirement for fuel cell containing CNT? This system needs a source of hydrogen, which can be stored inside the carbon
nanotubes.
24. Give some examples for catalytic reaction, carried out by using CNTs. (i) Reduction of nickel oxide(NiO) to the base metal Ni.
NiO C nanotubes Ni
(ii) Reduction of AlCl3 to its bases metal.
AlCl3 C nanotubes Al
25. How is pyrolysis carried out?
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Carbon nanotubes are synthesized by the pyrolysis of hydrocarbons such as
acetylene at about 700 degree centigrade in the presence of Fe-silica or Fe-graphite
catalyst under inert conditions.
26.How is CNT produced in carbon arc method? It is carried out by applying direct current (60-100 A and 290-25 V) arc between
graphite electrodes of 10-20 m diameter.
27. Mention some important applications of CNTs. 1. It is used in storage devices.
2. It is used as catalyst.
3. ?It is used as protective shields.
4. It is a very good reinforcing element in composites.
5. It is used as sensor for gases like NO2 and NH3.
PART- B
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UNIT I
WATER TECHNOLOGY
1. How the alkalinity of a water sample is estimated volumetrically?
2. Explain the aim, principle, procedure, calculation involved in EDTA method?
3. Write a note of boiler problems?
4. What is ion exchange method? Explain the concept.
5. What is reverse osmosis? Bring out the methodology behind it.
6. How will you treat the water for drinking purpose?
7. What are boiler compounds? How are they used in internal water treatment?
UNIT II POLYMERS AND COMPOSITES 1. Write a note on addition polymerization. Differentiate it from condensation type.
2. Explain the steps involved in free radical mechanism.
3. Give the preparation, property, uses of PVC, Teflon and Polycarbonate.
4. Give the preparation, property, uses of Polyurethane, PET and nylon 6,6.
5. Differentiate thermo and thermoset plastics.
6. Differentiate engineering and commodity plastics.
7. Explain the mechanism, purpose and importance of vulcanization.
8. Differentiate raw and vulcanized rubber.
9. Explain the process of obtaining rubber from latex. What are the defects of raw rubber?
10. Write a note on any two synthetic rubbers.
11. Give a detailed note on different types of composites?
12. Explain about FRP and their applications.
UNIT – III
SURFACE CHEMISTRY
1. Differentiate physisorption and chemisorption?
2. Explain the factors affecting adsorption of gases on solids.
3. Explain the factors affecting adsorption of solutes from solutions.
4. What are the five types of isotherms possible? Draw and explain the cases with eg.
5. Derive Langmuir adsorption isotherm.
6. Bring out the role of adsorption in heterogeneous catalyst?
7. Explain the principle of adsorption in ion-exchange process of water treatment?
8. What are the common applications of adsorption?
9. How can the pollution be reduced by activated charcoal.
UNIT – IV
NON-CONVENTIONAL ENERGY SOURCES/ STORAGE DEVICES
1. What is a nuclear chain reaction? Explain the basic principles and characteristics of it.
2. Explain light water power plant with a neat sketch.
3. Explain the significance and working principles of breeder reactor with necessary equations and
sketches.
4. Write an elaborate note on solar energy harnessing and applications.
5. Write a note on wind energy.
6. Explain the construction of O2-H2 fuel cells. State itsadvantages?
7. Explain the principle behind Lead acid accumulator.
8. What is the basic constructional idea behind NICAD battery?
9. Give the importance of Lithium battery. Explain the basic principles of it.
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UNIT – V
ENGINEERING MATERIALS
1. Classify the refractories. Explain one example for each type.
2. What are the properties of refractory? Explain any three of them.
3. Write notes on alumina, zirconia and magnesite bricks.
4. Write a note on synthetic abrasives.
5. What is your understanding about natural abrasives?
6. How will you explain the mechanism behind the lubrication?
7. Explain any four properties of lubricants?
8. How can you classify lubricants? Explain.
9. Write notes on solid lubricants.
10. Bring out the important applications of CNT.
11. Write a note on structure and synthesis of CNT.
All the best