engineering chemistry important 2 mark with answer.

CY21 51- ENGINEERING CHEMISTRY-I
QUESTION BANK
PART-A
UNIT-I
POLYMER CHEMISTRY
1. What is degree of polymerization?
No. of repeating units in a polymeric network.
2. Mention functionality of a monomer with suitable example.
No. of bonding or reactive site in a monomer.
3. What are co- polymers? Give example.
Formed by joining of two different monomer.
4. What are engineering plastics?
High molecular weight polymer resin posses mechanical strength toughness
durability.
5. What is a dead polymer?
The product of additional polymerization is known as dead polymer.s
6. Define Tacticity.
The orientation of monomeric units in a polymer is called tacticity.
7. Write any two thermal initiators used in thermal polymerization.
Acetyl peroxide & Benzoyl peroxide.
8. Mention the monomers which are polymerized in anionic polymerisation.
Acrylonitrite, methylacrylate, methylmethacrylate.
9. What are homochain and heterochain polymer?
Homochain: Addition polymer, Chain is made up of same type of atom
Heterochain: condensation polymer, Chain is made up of different types of atom
10.Why thermosetting plastics cannot be remolded?
Because the chains are joined by strong covalent force
UNIT-II
CHEMICAL THERMODYNAMICS
1. What is a system?
It is the part if the physical universe to which we direct out attention for the
purpose of experimental or theoretical investigation.
2. What is an extensive property?
An extensive property of a system depends upon the total amount of substance in
the system.
3. What is a process? Mention its type.
The operation which brings about the changes in the state of the system is called a
process. Types: i) Isothermal Process ii) Adiabatic process iii) cyclic process.
4. Define II law of thermodynamics?
Heat cannot of itself pass from colder to hotter body without the intervention of
any external agency.
5. What is Gibbs free energy?
The isothermally available energy present in a system is called free energy.
6. Mention any two applications of clausius.
 Molar Latent heat of vaporization can be calculated.
 To study the effect of pressure on boiling point.
7. Define work function?
The part of the internal energy which is isothermally available is called the work
function of the system.
8. Define entropy.
It is the measure of degree of disorder or randomness in a molecular system.
9. What is an adiabatic process?
A process is said to be adiabatic if no heat enters or leaves the system during any
step of the process.
10.Write the significance of vant’ hoff equation.
 To calculate ?H of a reaction by measuring the values of equilibrium
constant at two different temperatures.
 To calculate the value of equilibrium constant at a particular temperatures.
UNIT –III
PHOTOCHEMISTRY & SPECTROSCOPY
1. State Grothus –Draper Law.
Only the light that is absorbed by the substance can bring about a chemical change
in the substance.
2. State Starck- Einstein Law.
Each molecule taking part in a photochemical reaction absorbs one quantum of
radiation.
3. Write any two reasons for high quantum yield.
 Formation of intermediate product will act as a catalyst.
 Absobtion of raditions in the primary step produces atoms or free radicals
which initiate a series of chain reaction.
4. What is a photosensitiser?
The foreign substance which absorbs light radiation and transfers the absorbed
energy to the reactant is called photo sensitizer.
5. What is quenching?
When the foreign substance in the excited state colloids with another substance it
gets converted into some other product is called quenching.
6. What are chromophores? Give example.
The group (multiple bonds) which are the reason for colour of a compound.
-N=N-(azo).
7. Define the term bathochromic shift.
The shift of an absorbtion maximum towards longer wavelength is called
bathochromic or red shift.
8. What if finger print region?
The IR region 1400-700cm-1 gives very rich and intense absorption bands is called
finger print region.
9. Methane does not absorb IR energy. Why?
Because four hydrogen atoms of methane vibrate symmetrically.
10.What are the functions of auxochromes?
It deepens the color of the chromophore.
They are required to make the chromogen -a dye.
UNIT-IV
PHASE RULE & ALLOYS
1. State phase rule.
It explains the heterogeneous equilibrium. F=C-P+2.
2. Define phase.
Any homogeneous, physically distinct mechanically part of a system bound by a
boundary surface.
3. What is triple point?
Point where all three phases are at equilibrium.
4. Define degree of freedom.
Minimum numbers of variable (P, T, and C) which need to be define the state of
a system.
5. A system consists of benzene and water. What is the number of phases?
Two
6. Discuss the significance of eutectics mixture.
 We can predict the formation of solder.
 They are used in safety devices.
7. Mention some important properties of alloys.
Durability, Resists corrosion, Low electrical conductivity.
8. What are Stainless steels?
It is an alloy of Iron with Carbon which resists corrosion by atmosphere and
also by chemicals.
9. What is the main purpose of alloying steel?
 To resist corrosion and to improve the life time.
10. What are the basic differences between Steel and bronze?
Bronze has lower melting point than steel and also better heat than steel.
UNIT-V
NANOCHEMISTRY
1. Define Nanotechnology.
It is defined as the design, production, characterization and applications of

systems, structures and devices of nanometer size.
2. How are nanomaterial classified?
Nanomaterials with one dimension, Nanomaterials with two dimension,
nanomaterials with three dimension.
3. What are nanoparticles?
These are particles having three dimensional nanoscale. Eg. CaO, CdS.
4. What is a top down process?
Bulk materials are broken into nanosized particles in this method
5. What is a bottom up process?
Nanosized materials are produced by building up of atom by atom in this process.
6. What are nanotubes?
Nanotube has a nanometer scale tube like structure.
7. What are nanorods?
Nanomaterials having long sticks or rod shapes with diameter in nanoscale and a
length very much longer are called nanorods.
8. Mention any three uses of nanorods.
 In display technologies.
 In Energy harvesting.
 In LED
9. Mention any four methods used to synthesis nanomaterial.
 Precipitation
 Hydrothermal
 Solvothermal
 Thermolysis
10. Mention the various fields in which nanomaterials are used?
 Electrical and Electronic Devices.
 Memory Devices.
 Fuel Cells.
 Energy production.