1 . What is the crystallographic area of a pasta joint?
A. qual to the trigonometric ratio
B . Less than the trigonometric ratio
C . Greater than the trigonometric ratio
D. None of the above
Answer: Option (A) is equal to the trigonometric ratio.
Explanation: The crystallographic area of a pasta joint is equal to the trigonometric ratio, which is the ratio of the area of the joint to the area of the plane perpendicular to the joint.
2 . What is the volume of a pasta joint?
A . 2r³
B . (4/3)πr³
C . 4r²
D . 2πr
Answer: Option (B) is (4/3)πr³.
Explanation: The volume of a pasta joint can be calculated using the formula for the volume of a sphere, which is (4/3)πr³.
3 . The total surface area of a very long metal wire is?
A . πd²/4
B . πd
C . 2πd
D . 2πd²
Answer: Option (B) is πd.
Explanation: The total surface area of a long metal wire can be calculated using the formula for the circumference of a circle, which is 2πr or πd.
4 . If a metal wire has width b and length L, what is its total volume?
A . Lb
B . L²
C . Lb²
D . L³
Answer: Option (A) is Lb.
Explanation: The total volume of a metal wire can be calculated using the formula for the volume of a rectangular prism, which is L × b × h. Since the height of the wire is not given, we assume it is negligible.
5 . Which of the following is an example of a covalent solid?
A . Sodium chloride
B . Graphite
C . Copper
D . Aluminum oxide
Answer: Option (B) is graphite.
Explanation: Graphite is an example of a covalent solid because its atoms are held together by covalent bonds.
6 . Which of the following is not an example of an amorphous solid?
A . Glass
B . Rubber
C . Diamond
D . Plastic
Answer: Option (C) is diamond.
Explanation: Diamond is a crystalline solid, not an amorphous solid. The other options listed are all examples of amorphous solids.
7 . Which of the following statements is true about the melting point of a solid?
A . The melting point decreases with an increase in pressure.
B . The melting point increases with an increase in pressure.
C . The melting point is independent of pressure.
D . None of the above.
Answer: Option (B) is the melting point increases with an increase in pressure.
Explanation: The melting point of a solid increases with an increase in pressure because the solid becomes more stable at higher pressures.
8 . Which of the following is not a type of crystal defect?
A . Frenkel defect
B . Schottky defect
C . Amorphous defect
D . Vacancy defect
Answer: Option (C) is amorphous defect.
Explanation: Amorphous solids do not have a crystalline structure and therefore cannot have a crystal defect. The other options listed are all types of crystal defects.
9 . Which of the following is not a type of cubic crystal system?
A . Body-centered cubic
B . Face-centered cubic
C . Simple cubic
D . Hexagonal
Answer: Option (D) is hexagonal.
Explanation: Hexagonal is not a type of cubic crystal system. The other options listed are all types of cubic crystal systems.
10 . What is the formula for calculating the number of atoms in a unit cell?
A . Number of atoms = Z × (1/8)
B . Number of atoms = Z × (1/2)
C . Number of atoms = Z × (1/4)
D . Number of atoms = Z × (1)
Answer: Option (D) is Number of atoms = Z × (1).
Explanation: The formula for calculating the number of atoms in a unit cell is Number of atoms = Z × (1), where Z is the number of atoms per unit cell.
11 . What is the atomic radius of a metallic element in a face-centered cubic lattice?
A . 0.155r
B . 0.225r
C . 0.414r
D . 0.732r
Answer: Option (B) is 0.225r.
Explanation: The atomic radius of a metallic element in a face-centered cubic lattice is 0.225 times the edge length of the unit cell.
12 . What is the formula for calculating the density of a unit cell?
A . Density = (mass of unit cell) / (volume of unit cell)
B . Density = (mass of unit cell) × (volume of unit cell)
C . Density = (mass of unit cell) – (volume of unit cell)
D . Density = (mass of unit cell) + (volume of unit cell)
Answer: Option (A) is Density = (mass of unit cell) / (volume of unit cell).
Explanation: The formula for calculating the density of a unit cell is Density = (mass of unit cell) / (volume of unit cell).
13 . Which of the following is not a factor affecting the density of a unit cell?
A . Atomic mass
B . Atomic radius
C . Packing efficiency
D . Number of unit cells
Answer: Option (D) is number of unit cells.
Explanation: The number of unit cells does not affect the density of a unit cell. The other options listed are all factors that can affect the density of a unit cell.
14 . Which of the following statements is true about the density of a metallic crystal?
A . The density is always greater than the density of the metal in its liquid state.
B . The density is always less than the density of the metal in its liquid state.
C . The density is the same as the density of the metal in its liquid state.
D . The density of a metallic crystal cannot be compared to the density of the metal in its liquid state.
Answer: Option (A) is the density is always greater than the density of the metal in its liquid state.
Explanation: The density of a metallic crystal is always greater than the density of the metal in its liquid state because the atoms are packed more closely together in the solid state.
15 . Which of the following is not a type of interstitial solid solution?
A . Hydrogen in palladium
B . Nitrogen in iron
C . Carbon in iron
D . Copper in gold
Answer: Option (D) is copper in gold.
Explanation: Copper in gold is not an example of an interstitial solid solution. The other options listed are all examples of interstitial solid solutions.
16 . Which of the following is not a type of substitutional solid solution?
A . Copper in silver
B . Zinc in copper
C . Carbon in iron
D . Oxygen in magnesium
Answer: Option (D) is oxygen in magnesium.
Explanation: Oxygen in magnesium is not an example of a substitutional solid solution. The other options listed are all examples of substitutional solid solutions.
17 . Which of the following is not a property of ionic compounds?
A . High melting and boiling points
B . Brittle
C . Conductor of electricity in solid state
D . Soluble in polar solvents
Answer: Option (C) is conductor of electricity in solid state.
Explanation: Ionic compounds do not conduct electricity in the solid state. They conduct electricity only when they are in molten state or in solution.
18 . Which of the following is not a property of covalent compounds?
A . Low melting and boiling points
B . Insoluble in water
C . Poor conductor of electricity
D . High electronegativity
Answer: Option (D) is high electronegativity.
Explanation: Covalent compounds do not have high electronegativity. Electronegativity is a property of atoms, not compounds.
19 . Which of the following is a defect that arises due to the presence of an impurity in a crystal lattice?
A . Schottky defect
B . Frenkel defect
C . Vacancy defect
D . Interstitial defect
Answer: Option (A) is Schottky defect.
Explanation: Schottky defect is a type of point defect that arises due to the presence of an impurity in a crystal lattice.
20 . Which of the following is a type of non-stoichiometric defect?
A . Frenkel defect
B . Interstitial defect
C . Schottky defect
D . Metal excess defect
Answer: Option (D) is metal excess defect.
Explanation: Metal excess defect is a type of non-stoichiometric defect.
21 . Which of the following defects does not contribute to the electrical conductivity of a crystal?
A . Frenkel defect
B . Interstitial defect
C . Schottky defect
D . Vacancy defect
Answer: Option (D) is vacancy defect.
Explanation: Vacancy defect does not contribute to the electrical conductivity of a crystal. The other options listed are defects that can contribute to electrical conductivity.
22 . Which of the following is a type of amorphous solid?
A . Diamond
B . Graphite
C . Glass
D . Sodium chloride
Answer: Option (C) is glass.
Explanation: Glass is an example of an amorphous solid.
23 . Which of the following is a characteristic of amorphous solids?
A . They have a definite shape.
B . They have a regular arrangement of atoms.
C . They have a sharp melting point.
D . They lack a long-range ordered structure.
Answer: Option (D) is they lack a long-range ordered structure.
Explanation: Amorphous solids lack a long-range ordered structure, unlike crystalline solids.
24 . What is the difference between a crystalline solid and an amorphous solid?
A . Crystalline solids have a regular arrangement of atoms, while amorphous solids do not.
B . Crystalline solids are always transparent, while amorphous solids are always opaque.
C . Crystalline solids have a lower density than amorphous solids.
D . Crystalline solids are always brittle, while amorphous solids are always ductile.
Answer: Option (A) is Crystalline solids have a regular arrangement of atoms, while amorphous solids do not.
Explanation: Crystalline solids have a regular, repeating arrangement of atoms or molecules, while amorphous solids lack this order and have a random arrangement of particles.
25 . Which of the following is not a type of crystal structure?
A . Body-centered cubic
B . Face-centered cubic
C . Hexagonal close-packed
D . Simple cubic
Answer: Option (D) is simple cubic.
Explanation: Simple cubic is a type of crystal lattice, not a crystal structure.
26 . Which of the following elements does not have a face-centered cubic crystal structure?
A . Copper
B . Gold
C . Silver
D . Iron
Answer: Option (D) is iron.
Explanation: Iron has a body-centered cubic crystal structure, not a face-centered cubic structure.
27 . Which of the following statements is true about polymorphism?
A . It is the ability of a substance to exist in more than one crystal structure.
B . It is the ability of a substance to exist in both solid and liquid states.
C . It is the ability of a substance to form non-stoichiometric compounds.
D . It is the ability of a substance to form alloys with other elements.
Answer: Option (A) is It is the ability of a substance to exist in more than one crystal structure.
Explanation: Polymorphism is the ability of a substance to exist in more than one crystal structure.
28 . Which of the following is an example of a polymorph?
A . Graphite and diamond
B . Salt and sugar
C . Copper and gold
D . Oxygen and nitrogen
Answer: Option (A) is graphite and diamond.
Explanation: Graphite and diamond are examples of polymorphs of carbon.
29 . Which of the following is a characteristic of a unit cell?
A . It is the smallest repeating unit of a crystal lattice.
B . It is a two-dimensional representation of a crystal structure.
C . It is a type of point defect in a crystal.
D . It is a non-stoichiometric compound.
Answer: Option (A) is it is the smallest repeating unit of a crystal lattice.
Explanation: A unit cell is the smallest repeating unit of a crystal lattice, containing all the information needed to construct the entire lattice.
29 . Which of the following is not a type of crystal system?
A . Orthorhombic
B . Hexagonal
C . Quadrilateral
D . Triclinic
Answer: Option (C) is quadrilateral.
Explanation: Quadrilateral is not a type of crystal system. The other options listed are all types of crystal systems.
30 . Which of the following is not a characteristic of a cubic crystal system?
A . All sides are equal in length.
B . All angles are equal to 90 degrees.
C . It has only one type of symmetry axis.
D . It has three mutually perpendicular axes.
Answer: Option (C) is it has only one type of symmetry axis.
Explanation: The cubic crystal system has three types of symmetry axes: four-fold, three-fold, and two-fold.
31 . Which of the following statements is true about the Bravais lattice?
A . It is a two-dimensional representation of a crystal structure.
B . It describes the arrangement of atoms or molecules within a unit cell.
C . It is a type of point defect in a crystal.
D . It is a non-stoichiometric compound.
Answer: Option (B) is it describes the arrangement of atoms or molecules within a unit cell.
Explanation: The Bravais lattice describes the arrangement of atoms or molecules within a unit cell.
32 . Which of the following is not a type of point defect in a crystal?
A . Vacancy defect
B . Interstitial defect
C . Schottky defect
D . Frenkel defect
Answer: None of the options are correct.
Explanation: All the options are types of point defects in a crystal.
33 . Which of the following is not a type of dislocation in a crystal?
A . Edge dislocation
B . Screw dislocation
C . Mixed dislocation
D . Interstitial dislocation
Answer: Option (D) is interstitial dislocation.
Explanation: Interstitial dislocation is not a type of dislocation in a crystal.
34 . Which of the following is a type of imperfection in a crystal that causes a shift in the lattice planes?
A . Point defect
B .Dislocation
C . Polymorphism
D . Schottky defect
Answer: Option (B) is dislocation.
Explanation: Dislocations are imperfections in a crystal that cause a shift in the lattice planes.
35 . Which of the following is a type of imperfection in a crystal that involves a missing atom or ion?
A . Point defect
B . Dislocation
C . Polymorphism
D .Schottky defect
Answer: Option (A) is point defect.
Explanation: Point defects involve a missing or extra atom or ion in a crystal.
36 . Which of the following is a type of imperfection in a crystal that involves a vacancy and an interstitial site?
A . Point defect
B . Dislocation
C . Polymorphism
D . Schottky defect
Answer: Option (D) is Schottky defect.
Explanation: Schottky defects involve a paired vacancy and interstitial site.
37 . Which of the following is a type of imperfection in a crystal that involves an extra atom or ion?
A . Frenkel defect
B . Schottky defect
C . Edge dislocation
D . Screw dislocation
Answer: Option (A) is Frenkel defect.
Explanation: Frenkel defects involve an extra atom or ion in a crystal that occupies an interstitial site.
38 . Which of the following is a type of imperfection in a crystal that involves a shift in the lattice planes along a particular direction?
A . Edge dislocation
B . Screw dislocation
C . Mixed dislocation
D . Interstitial dislocation
Answer: Option (B) is screw dislocation.
Explanation: Screw dislocations involve a shift in the lattice planes along a particular direction.
39 . What is the coordination number of a face-centered cubic (FCC) crystal lattice?
A . 4
B . 6
C . 8
D . 12
Answer: Option (C) is 8.
Explanation: The coordination number of a face-centered cubic (FCC) crystal lattice is 8.
40 . What is the coordination number of a body-centered cubic (BCC) crystal lattice?
A. 4
B . 6
C . 8
D . 12
Answer: Option (B) is 6.
Explanation: The coordination number of a body-centered cubic (BCC) crystal lattice is 6.
41 . What is the coordination number of a simple cubic crystal lattice?
A . 4
B . 6
C . 8
D . 12
Answer: Option (A) is 4.
Explanation: The coordination number of a simple cubic crystal lattice is 4.
42 . Which of the following is not a characteristic of a crystalline solid?
A . Long-range order
B . Definite shape
C . Definite volume
D . Random arrangement of atoms
Answer: Option (D) is random arrangement of atoms.
Explanation: A characteristic of a crystalline solid is long-range order, definite shape, and definite volume, but not a random arrangement of atoms.
43 . Which of the following is not a characteristic of an amorphous solid?
A . Long-range order
B . Definite shape
C . Definite volume
D . Random arrangement of atoms
Answer: Option (A) is long-range order.
Explanation: An amorphous solid does not have long-range order, but has a definite shape and volume and a random arrangement of atoms.
44 . What is the difference between a crystal and an amorphous solid?
A . A crystal has a definite shape, while an amorphous solid does not.
B . A crystal has long-range order, while an amorphous solid does not.
C . A crystal has a random arrangement of atoms, while an amorphous solid has long-range order.
D . A crystal has a disordered arrangement of atoms, while an amorphous solid has long-range order.
Answer: Option (B) is a crystal has long-range order, while an amorphous solid does not.
Explanation: A crystal has long-range order, while an amorphous solid does not have a long-range order.
45 . Which of the following is not a type of point defect in a crystal lattice?
A . Vacancy defect
B . Interstitial defect
C . Substitutional defect
D . Line defect
Answer: Option (D) is line defect.
Explanation: The three types of point defects in a crystal lattice are vacancy defect, interstitial defect, and substitutional defect. Line defect is not a type of point defect, but a type of crystallographic defect that occurs along a line in a crystal lattice.
46 . Which of the following point defects increases the density of a crystal lattice?
A . Vacancy defect
B . Interstitial defect
C . Substitutional defect
D . None of the above
Answer: Option (B) is interstitial defect.
Explanation: An interstitial defect, where an extra atom is present in the interstitial site of the crystal lattice, increases the density of the crystal lattice.
47 . Which of the following point defects decreases the density of a crystal lattice?
A . Vacancy defect
B . Interstitial defect
C . Substitutional defect
D . None of the above
Answer: Option (A) is vacancy defect.
Explanation: A vacancy defect, where an atom is missing from its lattice site, decreases the density of the crystal lattice.
48 . Which of the following point defects does not change the stoichiometry of a crystal lattice?
A . Vacancy defect
B . Interstitial defect
C . Substitutional defect
D . All of the above
Answer: Option (A) is vacancy defect.
Explanation: Vacancy defect does not change the stoichiometry of the crystal lattice, while both interstitial and substitutional defects do.
49 . Which of the following point defects is responsible for the color of gemstones?
A . Vacancy defect
B . Interstitial defect
C . Substitutional defect
D . Line defect
Answer: Option (C) is substitutional defect.
Explanation: Substitutional defects, where one type of atom is replaced by another type of atom in the crystal lattice, is responsible for the color of many gemstones.
50 . Which of the following point defects is responsible for electrical conductivity in semiconductors?
A . Vacancy defect
B . Interstitial defect
C . Substitutional defect
D . All of the above
Answer: Option (B) is interstitial defect.
Explanation: Interstitial defects, where an extra atom is present in the interstitial site of the crystal lattice, is responsible for electrical conductivity in semiconductors.