Tag: materials

Quizzes (22) Questions (81)

Questions Related to materials

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

Which of the following is true?

  1. The surface of quantum dot can be chemically modified by attaching on organic molecule.

  2. When modified quantum dots bound to a bio-molecule are irradiated with UV light they emit light of a particular wavelength dependent on size of quantum dots.

  3. The modified quantum dots are thousand times smaller than the human cells.

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All of the given statements are true.
The surface of a quantum dot can be chemically modified by attaching an organic molecule. A modified quantum dot targets and forms a chemical bond with a specific biomolecule such as DNA or protein.
The modified quantum dots are thousand times smaller than the human cells. They can easily penetrate cell membranes.
When modified quantum dots bound to a bio-molecule are irradiated with UV light they emit light of a particular wavelength dependent on size of quantum dots. 
If a mixture of quantum dots of different size and different surface modifications are irradiated with a single light source, the detection tracking and having coloured images of a number of different biomolecules within a cell is possible.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

In future nanomaterials can be used to detect human cancer at its __________.

  1. earliest and most curable stages

  2. last stage

  3. intermediate stages

  4. all stages
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In future nanomaterials can be used to detect human cancer at its earliest and most curable stages. Currently, the application of various nanoparticles (including quantum dots) for cancer detection and treatment is under study.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

Which of the following are applications of carbon nano tubes?

  1. Catalysis

  2. Biosensor

  3. Drug carriers

  4. All the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

As a result of their good physical and chemical properties such as the strongest and stiffest materials yet discovered in terms of tensile strength and elastic modulus respectively and good electrical and thermal conductor, carbon nano tubes have potential use in a variety of industrial and biomedical applications including: Catalysis, Biosensor, Drug carriers composite materials with improved mechanical and electrical properties. Hence option D is correct

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

Nano science deals with the scientific study of objects with sizes in the ____ range in at least one dimension.

  1. 200-300 nm

  2. 100-1000 nm

  3. 1-100 nm

  4. 400-500 nm
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Nanoscience deals with the scientific study of objects with sizes in the 1-100 nm range in one dimension.


Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

In which of the following type of nano material all the dimensions are measured within the nano scale?

  1. Zero dimensional naomaterial

  2. one dimensional naomaterial

  3. Two dimensional naomaterial

  4. Three dimensional naomaterial
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Accordingly, in zero-dimensional (0D) nanomaterials all the dimensions are measured within the nanoscale (no dimensions are larger than 100 nm). Most commonly, 0D nanomaterials are nanoparticles.
Hence option A is correct.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

In which of the following type of nano material two  dimensions are outside the nano scale?

  1. One dimensional nano material

  2. Two dimensional nano material

  3. Three dimensional nano material

  4. Zero dimensional nano material
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In two-dimensional nanomaterials (2D), two dimensions are outside the nanoscale.This class exhibits plate-like shapes and includesgraphene, nanofilms, nanolayers, and nanocoatings.
Hencce option B is correct.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

Which of the following nano materials are examples of  two dimensional nano materials?

  1. nanocoatings.

  2. nanofilms, nanolayers

  3. graphene,

  4. A,B,C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

n two-dimensional nanomaterials (2D), two dimensions are outside the nanoscale. This class exhibits plate-like shapes and includes graphene, nanofilms, nanolayers, and nanocoatings.
Hence option D is correct.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

An important parameter that determines the functioning of nano material is surface area to volume ratio. Because of which reason small granules of sugar dilute faster than big piece of sugar cube?

  1. SA/V ratio of sugar granules is smaller than sugar cube.

  2. Can not say anything without knowing temperature of solvent.

  3. SA/V ratio is same for sugar and sugar cube.

  4. SA/V ratio of sugar granules is greater than sugar cube.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

SA/V ratio of sugar granules is greater than sugar cube so in Sugar granules, a greater portion of sugar atoms will be on surface so contact with water will be more as compared to sugar cube and it will dissolve faster than big piece of sugar cube.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

Thus nanoparticles have a much ____________ surface area per unit mass compared with larger particles.

  1. Greater

  2. Lesser

  3. Equal

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Two principal factors cause the properties of nanomaterials to differ significantly from other materials: increased relative surface area, and quantum effects. These factors can change or enhance properties such as reactivity, strength and electrical characteristics.

As a particle decreases in size, a greater proportion of atoms are found at the surface compared to those inside. For example, a particle of size 30 nm has 5% of its atoms on its surface, at 10 nm 20% of its atoms, and at 3 nm 50% of its atoms.

Thus nanoparticles have a much greater surface area per unit mass compared with larger particles. As growth and catalytic chemical reactions occur at surfaces, this means that a given mass of material in nanoparticulate form will be much more reactive than the same mass of material made up of larger particles.

Multiple choice nanochemistry nanotechnology applied chemistry materials chemistry

In which of the following type of nano-material, one dimension is outside the nano scale?

  1. One dimensional nano material

  2. Two dimensional nano material

  3. Three dimensional nano material

  4. Zero dimensional nano material
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In one-dimensional nanomaterials (1D), one dimension is outside the nanoscale. This class includes nanotubes, nanorods, and nanowires.
Hence option A is correct.