Chemistry

Solid State and Crystal Structures

198 Questions

Solid state chemistry focuses on the structural properties of crystalline solids. Questions cover Bravais lattices, unit cells, and close packed structures. This topic is essential for chemistry papers in UPSC and state PSC examinations.

Bravais lattice typesUnit cell calculationsClose packed structuresCrystal densityBragg's LawWurtzite structure

Solid State and Crystal Structures Questions

Multiple choice chemistry solid state classification of crystalline solids classification of solids introduction to solids
In a cubic structure of diamond which is made from X and Y, where X atoms are at the corners of the cube and Y at the face centres of the cube. The molecular formula of the compound is
  1. $X _2Y$
  2. $X _3Y$
  3. $XY _2$
  4. $XY _3$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In a cubic unit cell, corner atoms (X) contribute 8 * (1/8) = 1 atom. Face-centered atoms (Y) contribute 6 * (1/2) = 3 atoms. The ratio of X to Y is 1:3, resulting in the formula XY3.

Multiple choice

What is the primary mechanism responsible for the gas sensing properties of certain ceramic functional materials?

  1. Chemisorption

  2. Physisorption

  3. Redox reactions

  4. Structural changes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In ceramic gas sensors, the gas sensing properties often arise from chemisorption, where gas molecules react with the surface of the ceramic material, leading to changes in electrical or optical properties.

Multiple choice

The Miller indices of a crystal plane are represented by three integers, (h, k, l). What do these integers represent?

  1. The intercepts of the plane with the crystallographic axes

  2. The angles between the plane and the crystallographic axes

  3. The lengths of the edges of the unit cell

  4. The atomic positions within the unit cell
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Miller indices (h, k, l) represent the intercepts of the crystal plane with the crystallographic axes a, b, and c, respectively.

Multiple choice

In the context of crystallography, what is the term 'Bragg's Law' associated with?

  1. The relationship between the wavelength of X-rays and the diffraction angle

  2. The relationship between the energy of electrons and the diffraction angle

  3. The relationship between the temperature of a crystal and its lattice spacing

  4. The relationship between the pressure of a crystal and its lattice spacing
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bragg's Law describes the relationship between the wavelength of X-rays and the diffraction angle in X-ray crystallography.

Multiple choice

What is the basic repeating unit of a crystal lattice?

  1. Atom

  2. Molecule

  3. Unit cell

  4. Ion
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A unit cell is the smallest repeating unit of a crystal lattice that retains the symmetry of the crystal.

Multiple choice

Which of the following is a type of crystal structure?

  1. Cubic

  2. Hexagonal

  3. Tetragonal

  4. Orthorhombic
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

Cubic, hexagonal, tetragonal, and orthorhombic are all types of crystal structures.

Multiple choice

What is the Bravais lattice?

  1. A lattice with a repeating pattern of points

  2. A lattice with a repeating pattern of unit cells

  3. A lattice with a repeating pattern of atoms

  4. A lattice with a repeating pattern of molecules
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Bravais lattice is a lattice with a repeating pattern of points that represent the positions of atoms or molecules in a crystal.

Multiple choice

What is the effect of firing pottery at a high temperature?

  1. Creates a stronger and more durable pottery

  2. Creates a more porous pottery

  3. Creates a pottery with a metallic sheen

  4. Creates a pottery with a matte finish
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Firing pottery at a high temperature creates a stronger and more durable pottery.

Multiple choice

What is the effect of firing pottery at a low temperature?

  1. Creates a weaker and less durable pottery

  2. Creates a more porous pottery

  3. Creates a pottery with a metallic sheen

  4. Creates a pottery with a matte finish
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Firing pottery at a low temperature creates a weaker and less durable pottery.

Multiple choice

Which of the following is a type of crystal lattice structure?

  1. Cubic

  2. Hexagonal

  3. Tetragonal

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

Cubic, hexagonal, and tetragonal are all types of crystal lattice structures, which are regular arrangements of atoms, molecules, or ions in a solid material.

Multiple choice

Which of the following is an example of a solid-state phase transformation?

  1. Melting

  2. Solidification

  3. Annealing

  4. Tempering
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Annealing is a solid-state phase transformation that involves heating a metal to a specific temperature and then slowly cooling it to relieve internal stresses and improve its ductility.

Multiple choice

What is a stacking fault?

  1. A region of a crystal where the atoms are arranged in a different order than the rest of the crystal

  2. A boundary between two grains in a polycrystalline material

  3. A linear defect in a crystal where atoms are misaligned

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

A stacking fault is a region of a crystal where the atoms are arranged in a different order than the rest of the crystal. It can be caused by the movement of atoms during crystal growth, or by the application of stress to a crystal.

Multiple choice

Which of the following is a type of semiconductor material?

  1. Silicon (Si)

  2. Germanium (Ge)

  3. Gallium Arsenide (GaAs)

  4. Copper (Cu)

  5. Aluminum (Al)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Silicon is a widely used semiconductor material due to its abundance, relatively low cost, and well-understood properties.

Multiple choice

Which of the following is an example of a substance that has a triple point at room temperature and pressure?

  1. Water

  2. Carbon Dioxide

  3. Sodium Chloride

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

Water is a substance that has a triple point at room temperature and pressure, meaning it can exist in all three phases simultaneously under these conditions.