Nano Materials

Question 1

Nanomaterials are the materials with at least one dimension measuring less than ___________
a) 1 nm
b) 10 nm
c) 100 nm
d) 1000 nm

Answer 1

100 nm

Question 2

A material with one dimension in Nano range and the other two dimensions are large is called ___________
a) Micro-material
b) Quantum wire
c) Quantum well
d) Quantum dot

Answer 2

Quantum well

A material with two of the three dimensions in the nano range and third large is called quantum wire. When all the dimensions are in nano range, it is called quantum dot.

Question 3

The colour of the nano gold particles is ___________
a) Yellow
b) Orange
c) Red
d) Variable

Answer 3

Variable

The colour of the nano gold particle varies with the size of the particles. It shows different colours like orange, red, purple, or greenish.

Question 4

The melting point of particles in nano form ___________
a) Increases
b) Decreases
c) Remains same
d) Increases then decreases

Answer 4

Decreases

For the particles in the nano form, the melting point reduces significantly. Other chemical properties are also changed as the dimensions of the object comes in the nano range.

Question 5

The first talk about nano-technology was given by ___________
a) Albert Einstein
b) Newton
c) Gordon E. Moore
d) Richard Feynman

Answer 5

Richard Feynman

In 1959, Richer Feynman gave a speech in which he spoke of nano-science and nano-technology. He talked about the possibility of manipulating individual atoms and molecules.

Question 6

Which of the processes of materials was not described as Nanotechnology?
a) Separation
b) Creation
c) Processing
d) Consolidation

Answer 6

Creation

Nanotechnology, as defined by Professor N. Taniguchi, consists of the processing, separation, consolidation and deformation of materials by one atom or by one molecule. It is used exclusively for the nanomaterials.

Question 7

The initial tools used to help launch the nanoscience revolution were ___________
a) Binoculars
b) Microscope
c) Scanning probe instruments
d) Interferometer

Answer 7

Scanning probe instruments

In these instruments, the probe slides along the surface of the specimen.

Question 7

When semiconductors are reduced to nanometres they become pure conductors.
a) True
b) False

Answer 7

False

When semiconductors are reduced to the nano form their chemical properties change significantly and they become insulators, as there is no more space for free electrons to move.

Question 8

The major difference between the nano materials compared to the bulk form is the big fraction of the total number of atoms on the surface.
a) True
b) False

Answer 8

True

As the bulk material is changed into nano form, the number of atoms on the surface turns out to be a large fraction of the total number of atoms present in the material. Due to this, the whole physical/chemical properties of the material changes.

Question 9

The size of atoms is nearly ____________
a) 0.01 nm
b) 0.1 nm
c) 1 nm
d) 10 nm

Answer 9

0.1 nm

Question 10

What’s the procedure in Top-down fabrication method?
a) Nano-particles -> Powder -> Bulk
b) Powder -> Bulk – > Nano-particles
c) Bulk -> Powder – > Nano-particles
d) Nano-particle – > Bulk -> Powder

Answer 10

Bulk -> Powder – > Nano-particles

In the bottom-up approach, the atoms are joined to form nano-particles.

Question 11

Which of the following is an example of Bottom Up approach?
a) Attrition
b) Colloidal dispersion
c) Milling
d) Etching

Answer 11

Colloidal dispersion

Attrition, milling and etching are typical top down methods.

Question 12

For milling operations, what kind of environment is preferred?
a) Acidic
b) Basic
c) Active
d) Inert

Answer 12

Inert

Milling is the process of particle size reduction with the objective of mixing or blending and change of particle size. An inert environment is preferred for this process.

Question 13

What kind of metals are used for milling operations?
a) Soft and brittle
b) Soft and elastic
c) Hard and brittle
d) Hard and elastic

Answer 13

Hard and brittle

Question 14

The water is prepared and then photoresist is applied. The product is exposed to the UV light which after a series of processes, results in the fabrication of nanomaterials.

What is the above method called

Answer 14

Microfabrication

Question 15

CVD stands for ____________
a) Carbon vapour density
b) Chemical vapour density
c) Chemical vapour deposition
d) Carbon vapour deposition

Answer 15

Chemical vapour deposition

CVD, is a chemical process used to produce high-purity, high-performance solid materials. The process is often used to produce carbon nanotubes.

Question 16

Photolithography is a type of patterning technique.
a) True
b) False

Answer 16

True

Question 17

Chemical solution deposition is also known as ____________
a) Sol-gel
b) CVD
c) Plasma spraying
d) Laser pyrolysis

Answer 17

Sol-gel

Sol-gel, or chemical solution deposition, is used primarily for the fabrication of material starting from a chemical solution that acts as the precursor for an integrated network.

Question 18

Typical precursor used in sol-gel are ____________
a) Metal oxides
b) Metal dioxides
c) Metal alkoxides
d) Metal fluorides

Answer 18

Metal alkoxides

Metal alkoxides and metal chlorides are basically used as precursors in sol-gel. Furthermore, a colloidal suspension is formed when they undergo hydrolysis or poly-condensation.

Question 19

Particles of ZrO2, Y2O2 and Nano whiskers have been produced by __________
a) Sol-gel
b) CVC
c) Plasma spraying
d) Laser pyrolysis

Answer 19

CVC

CVC stands for chemical vapour condensation. It involves pyrolysis of vapours of metal organic precursors in a reduced pressure atmosphere.

Question 20

Which gas serves as buffer gas in Laser ablation?
a) Nitrogen
b) Oxygen
c) Helium
d) Neon

Answer 20

Helium

Laser ablation has been extensively used for the preparation of nanoparticles. In the device, there is a pulsed flow of Helium gas. It serves as a buffer gas in which clusters of the target material form, thermalize.

Question 21

1. The configuration of Buckminsterfullerene is ____________
   a) 12 Hexagons and 22 Pentagons
   b) 18 Hexagons and 15 Pentagon
   c) 20 Hexagon and 12 Pentagon
   d) 15 Hexagon and 15 Pentagon

Answer 21

20 Hexagon and 12 Pentagon

Question 22

C60 is soluble in ____________
a) Water
b) Ammonia
c) HCl
d) Benzene

Answer 22

Benzene

C60 molecules are held together by weak Van der Waal’s forces. They are insoluble in ionic solvents like water, ammonia and HCl, as it is non-ionic. As it is an organic molecule, it is soluble in Benzene.

Question 23

CNTs are capped on both ends with which carbon nanostructure?
a) Graphite
b) Diamond
c) C60
d) Benzene

Answer 23

C60

Carbon Nanotubes are basically a single sheet of graphite, which is rolled into a tube. The ends of the CNTs are covered by the C60 hemispheres.

Question 24

For the synthesis of CNTs, the quartz tube is heated up to ____________ a) 1000℃ b) 1200℃ c) 1400℃ d) 1600℃

Answer 24

1200℃ For the synthesis of CNTs, a quartz tube containing argon gas and a graphite target are heated to 1200o C. This process takes place by the use of lasers.

Question 25

The metallic tubes have which kind of structure? a) Armchair b) Chiral c) Boat d) Achiral

Answer 25

Armchair The CNTs are often a mixture of semiconducting and metallic tubes. While the metallic tubes have armchair structure, the semiconducting tubes have a chiral structure.

Question 26

The carbon tubes have high conductivity. a) True b) False

Answer 26

True The reason for the high conductivity of the carbon nanotubes is that they have very few defects to scatter electrons and therefore show very low resistance.

Question 27

Carbon nanotubes display magnetoresistance at low temperature. a) True b) False

Answer 27

True Magnetoresistance is the phenomenon in which the resistance of a material changes on the application of a magnetic field. Carbon nanotubes display this property at low temperature. In fact, it shows negative magnetoresistance as the resistance decreases with an increasing magnetic field.

Question 28

The main purpose of CNTs in fuel cells is ___________ a) Production of energy b) Active medium c) Catalyst d) Storage

Answer 28

Storage Carbon nanotubes are useful in fuel cells as well as in batteries, primarily for storage purposes of hydrogen. The tubes need to hold 6.5% hydrogen by weight.

Question 29

Carbon nanotubes are poor transmitters of electromagnetic radiations due to their ____________ a) High conductivity b) Large surface area c) High porosity d) Chemical Stability

Answer 29

High conductivity Carbon nanotubes have very high electrical conductivity. Due to this, they are poor transmitters of electromagnetic radiations. A plastic composite of CNTs could provide lightweight shielding material for electromagnetic radiation.

Question 30

The four types of Artificial nanomaterials are __________ a) Carbon-based, non-metallic, composites and ceramics b) Carbon-based, metallic, composites and ceramics c) Carbon-based, non-metallic, composites and dendrimers d) Carbon-based, metallic, composites and dendrimers

Answer 30

Carbon-based, metallic, composites and dendrimers

Question 31

olution of pure buckminsterfullerene has a colour of ___________ a) Green b) Purple c) Pink d) Yellow

Answer 31

Purple

Question 32

HyFn stands for __________ a) Hydrated Fluorine b) Hydrolysed Fluorine c) Hydrolysed Fullerene d) Hydrated Fullerene

Answer 32

Hydrated Fullerene HyFn stands for Hydrated fullerene. It is a stable, highly hydrophilic, super-molecular complex consisting of C60 molecules.

Question 33

Nano sized polymers built from branched units are called __________ a) Dendrimers b) Composites c) Carbon-based materials d) Metal-based materials

Answer 33

Dendrimers

Question 34

Which property of nanoparticles provides a driving force for diffusion? a) Optical Properties b) High surface area to volume ratio c) Sintering d) There is no such property

Answer 34

High surface area to volume ratio

Question 35

Quantum dots can be used in _________ a) Crystallography b) Optoelectronics c) Mechanics d) Quantum physics

Answer 35

Optoelectronics Quantum dots are basically semiconductor nanoparticles that show a particular colour on illumination by a light. They have unique electrical and optical properties. Due to this, they are widely used in optoelectronics.

Question 36

Vesicle is a type of __________ a) Nanostructure b) Nanoparticle c) Nanocrystal d) Supramolecular system

Answer 36

Supramolecular system Vesicle is a bubble of liquid within another liquid, a supramolecular assembly made up of man different molecules. They can be formed naturally as well as artificially.

Question 37

Which property of Nanomaterials make them suitable to be used for elimination of pollutants? a) High purity b) Better thermal conductivity c) Enhanced chemical activity d) Small size

Answer 37

Enhanced chemical activity

Question 38

Nano crystalline materials synthesised by sol-gel technique results in a foam like structures called ___________ a) Gel b) Aerosol c) Foam d) Aerogel

Answer 38

Aerogel The foam-like material formed is called aerogel. They are porous and extremely lightweight, yet they can load equivalent to 100 times their weight. They are used as insulation materials.

Question 39

Which nanomaterial is used for cutting tools? a) Fullerene b) Aerogel c) Tungsten Carbide d) Gold

Answer 39

Tungsten Carbide

Question 40

Aerogels can hold more energy than the separators in batteries. a) True b) False

Answer 40

True The energy density of a conventional battery is quite low. The Nano crystalline materials, as aerogels, have considerably more energy holding capacity.

Question 41

A Carbon monoxide sensor made of zirconia uses which characteristic to detect any change? a) Capacitance b) Resistivity c) Activity d) Permeability

Answer 41

Activity Zirconia uses its chemical activity to sense the presence of CO. In case CO is present, the oxygen atoms in zirconia would react with the carbon in CO to partially reduce Zirconium oxide.

Question 42

Which components of an automobile are envisioned to be coated with zirconia? a) Spark plugs b) Liners c) Tyres d) Brakes

Answer 42

Liners Zirconia is a hard and brittle ceramic. Its use in the coating of liners in an automobile is envisioned, as it can heat up the engine more effectively. Alumina can also be used for coating.

Question 43

The main purpose of CNTs in fuel cells is __________ a) Production of energy b) Active medium c) Catalyst d) Storage

Answer 43

Storage

Question 44

Nanoscale aluminium oxide increases the _________ a) Conductivity b) Resistance c) Ductility d) Stability

Answer 44

Resistance Nanoscale aluminium oxide and titanium oxide are optically transparent and they greatly increase abrasion resistance of traditional coatings.

Question 45

Which one of the following is an example for top-down approach? Ball milling technique Sol-gel process Both a and b None of the above

Answer 45

Ball milling technique

Question 46

The measurement range of electron microscopy is around _____________ meters? a. 1 m b. 1 nm c. 10 m d. 12 mm

Answer 46

1 nm

Question 47

Which one of the following neurotoxic effects comes under gold nanoparticles? a. Cognition defects b. Necrosis c. Genotoxicity d. None of the above

Answer 47

Cognition defect

Question 48

What is the dimensional classification of quantum dots?

Answer 48

0D

Question 49

What is the dimensional classification of quantum dots?

Answer 49

0D

Question 50

Which nanomaterial classification refers to nanosheets?

Answer 50

2D

Question 51

A bulk material with nanostructures inside is classified as?

Answer 51

3D

Question 52

Nanoparticles belong to which dimensional classification?

Answer 52

0D

Question 53

Which dimensional nanomaterials have length, width, and height all in the nanoscale?

Answer 53

0D

Question 54

What is the typical size range of nanomaterials?

Answer 54

1 to 100 nanometers

Question 55

Match the following a. CNT 1. 0D b. Fullerene 2. 1D c. Graphene 2. 2D

Answer 55

CNT - 1D Fullerene - 0D Graphene - 2D

Question 56

What kind of materials are typically synthesized using the sol-gel method?

Answer 56

Metal oxides

Question 57

In the sol-gel method, what is the role of water in the hydrolysis process?

Answer 57

It helps in the breakdown of the precursor compound.

Question 58

What is a common precursor used in the sol-gel synthesis of titanium dioxide?

Answer 58

Titanium alkoxide

Question 59

Which type of nanoparticles are commonly synthesized via chemical reduction?

Answer 59

Metal nanoparticles

Question 60

What is the diameter range of a single-walled carbon nanotube (SWCNT)?

Answer 60

1-2 nanometers

Question 61

Which type of carbon nanotube has superior electrical conductivity?

Answer 61

Single-walled carbon nanotubes (SWCNTs)

Question 62

What is the role of a stabilizing agent in the chemical reduction method? a) It accelerates the reduction reaction b) It prevents the aggregation of nanoparticles c) It increases the oxidation of metal ions d) It enhances the growth of nanoparticles

Answer 62

It prevents the aggregation of nanoparticles

Question 63

Which metal salt is commonly used as a precursor for the synthesis of silver nanoparticles via chemical reduction a) Silver nitrate (AgNO₃) b) Silver chloride (AgCl) c) Silver sulfate (Ag₂SO₄) d) Silver oxide (Ag₂O)

Answer 63

Silver nitrate (AgNO₃)

Question 64

What is a common characteristic of nanoparticles synthesized by the chemical reduction method? a) Large size variation b) Homogeneous particle distribution c) Irregular shapes d) High agglomeration

Answer 64

Homogeneous particle distribution

Question 65

Which of the following is a method used to synthesize carbon nanotubes? a) Sol-gel method b) Arc discharge method c) Ball milling d) Thermal evaporation

Answer 65

Arc discharge method

Question 66

What is the structure of graphene? a) 1D chain of carbon atoms b) 2D single layer of carbon atoms c) 3D crystalline form of carbon d) Spherical cluster of carbon atoms

Answer 66

2D single layer of carbon atoms

Question 67

What is the hybridization of carbon atoms in graphene? a) sp b) sp² c) sp³ d) sp⁴

Answer 67

Sp2

Question 68

Graphene is known for having which of the following properties? a) Poor electrical conductivity b) Exceptional electron mobility c) High density d) Low mechanical strength

Answer 68

Exceptional electron mobility

Question 69

What is a significant potential application of graphene in electronics? a) Superconducting materials b) Flexible touchscreens c) Photovoltaic cells d) Magnetic storage devices

Answer 69

b) Flexible touchscreens

Question 70

Fullerenes have potential applications in: a) Battery electrodes b) Superconductors c) Drug delivery systems d) All of the above

Answer 70

All of the above

Question 71

What makes fullerenes unique compared to other carbon allotropes? a) They have a two-dimensional structure b) They have a hollow, cage-like structure c) They are arranged in layers d) They have a hexagonal lattice

Answer 71

They have a hollow, cage-like structure

Question 72

Which property of fullerenes makes them suitable for drug delivery? A: a) High mechanical strength b) Ability to trap other atoms inside their structure c) High electrical conductivity d) High surface area

Answer 72

Ability to trap other atoms inside their structure

Question 73

The discovery of fullerenes was awarded the Nobel Prize in Chemistry in which year? a) 1980 b) 1996 c) 2000 d) 2010

Answer 73

1996

Question 74

Who is credited with the discovery of carbon nanotubes? a) Sumio Iijima b) Richard Smalley c) Andre Geim d) Harold Kroto

Answer 74

Sumio Iijima (1991)

Question 75

In which year were carbon nanotubes first observed by Sumio Iijima? a) 1985 b) 1991 c) 2004 d) 1996

Answer 75

1991

Question 76

What was the method used by Sumio Iijima to first observe carbon nanotubes? a) Chemical vapor deposition b) Arc discharge method c) Laser ablation d) Sol-gel process

Answer 76

Arc discharge method

Question 77

Who are the scientists credited with the isolation of graphene? a) Sumio Iijima and Richard Smalley b) Andre Geim and Konstantin Novoselov c) Harold Kroto and Robert Curl d) Thomas Swan and Richard Feynman

Answer 77

Andre Geim and Konstantin Novoselov

Question 78

In which year was graphene first isolated? a) 2000 b) 1991 c) 2004 d) 1996

Answer 78

2004

Question 79

What simple technique was used by Andre Geim and Konstantin Novoselov to isolate graphene? a) Chemical vapor deposition b) Electrochemical exfoliation c) Mechanical exfoliation (Scotch tape method) d) Ball milling

Answer 79

Mechanical exfoliation (Scotch tape method)

Question 80

For their groundbreaking work on graphene, Andre Geim and Konstantin Novoselov were awarded the Nobel Prize in Physics in: a) 2008 b) 2010 c) 2012 d) 2014

Answer 80

2010

Question 81

Who is credited with the discovery of fullerenes (C60)? a) Andre Geim b) Sumio Iijima c) Harold Kroto, Robert Curl, and Richard Smalley d) Konstantin Novoselov

Answer 81

arold Kroto, Robert Curl, and Richard Smalley

Question 82

In which year were fullerenes (C60) first discovered? a) 1985 b) 1991 c) 1996 d) 2000

Answer 82

1985

Question 83

Fullerenes were discovered using which technique? a) Chemical vapor deposition b) Arc discharge method c) Laser ablation d) Mechanical exfoliation

Answer 83

Laser ablation

Question 84

Harold Kroto, Robert Curl, and Richard Smalley received the Nobel Prize in Chemistry for their discovery of fullerenes in: a) 1985 b) 1996 c) 2004 d) 2010

Answer 84

1996

Question 85

What inspired the name "fullerene" for the C60 molecule? a) The structural similarity to geodesic domes designed by architect Buckminster Fuller b) Its ability to conduct electricity c) Its spherical shape d) Its high carbon content

Answer 85

The structural similarity to geodesic domes designed by architect Buckminster Fuller

Question 86

Which of the following is a commonly used reducing agent in the chemical reduction method? a) Sodium hydroxide (NaOH) b) Sodium borohydride (NaBH₄) c) Hydrochloric acid (HCl) d) Ethanol

Answer 86

b) Sodium borohydride (NaBH₄)

Question 87

Which of the following is NOT a commonly used reducing agent in nanomaterial synthesis? a) Ascorbic acid b) Sodium borohydride c) Hydrogen peroxide d) Hydrazine

Answer 87

Hydrogen peroxide

Question 88

Why is sodium borohydride commonly used as a reducing agent in the synthesis of nanoparticles? a) It is inexpensive b) It provides strong reducing power c) It acts as both a reducing and stabilizing agent d) It can be used at high temperatures

Answer 88

It provides strong reducing power

Question 89

What is the main purpose of using a surfactant in the chemical reduction method? a) To increase the reaction temperature b) To reduce the metal ions c) To control nanoparticle size and morphology d) To stabilize the metal ions

Answer 89

To control nanoparticle size and morphology

Question 90

What are the reagent used for chemical reduction method for producing Molybdenum Nano Particles

Answer 90

Molybdenum Chloride + Toluene + Sodium Borohydride

Question 91

What are the reagent used for chemical reduction method for producing Silver Nano Particles

Answer 91

Ascorbic acid as reducing agent and Sodium polyacrylate as protective agent