1. Which of the following is NOT a state of matter?
a) Solid
b) Liquid
c) Gas
d) Energy
Answer: d) Energy
Explanation: Energy is not matter; matter has mass and occupies space.
2. Matter is made up of _______.
a) Cells
b) Atoms
c) Molecules
d) Both b and c
Answer: d) Both b and c
Explanation: Matter is composed of atoms, which can form molecules.
3. Which of the following has a definite shape and definite volume?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: a) Solid
Explanation: Solids have fixed shape and volume due to strong intermolecular forces.
4. Which state of matter has neither definite shape nor definite volume?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: c) Gas
Explanation: Gases take the shape and volume of their container.
5. Which of the following is NOT an example of matter?
a) Air
b) Water
c) Sound
d) Ice
Answer: c) Sound
Explanation: Sound is a form of energy, not matter.
6. Which physical property is common to all states of matter?
a) Mass and volume
b) Shape
c) Rigidity
d) Color
Answer: a) Mass and volume
Explanation: All matter has mass and occupies space.
7. Which is the smallest particle of matter that retains its chemical properties?
a) Atom
b) Molecule
c) Electron
d) Nucleus
Answer: a) Atom
Explanation: Atoms are the basic units of chemical elements.
8. What is the SI unit of mass?
a) Gram
b) Kilogram
c) Pound
d) Newton
Answer: b) Kilogram
Explanation: Kilogram is the standard SI unit of mass.
9. Which state of matter has high compressibility?
a) Solid
b) Liquid
c) Gas
d) All of these
Answer: c) Gas
Explanation: Gases can be compressed easily due to large intermolecular spaces.
10. Which process converts a solid directly into gas?
a) Condensation
b) Sublimation
c) Evaporation
d) Fusion
Answer: b) Sublimation
Explanation: Sublimation is the direct change from solid to gas without passing through the liquid state.
11. Which property is related to the arrangement of particles in solids?
a) Fixed arrangement
b) Random arrangement
c) Loose arrangement
d) None of these
Answer: a) Fixed arrangement
Explanation: Solid particles are closely packed in a fixed arrangement.
12. Which state of matter can flow?
a) Solid
b) Liquid
c) Gas
d) Both b and c
Answer: d) Both b and c
Explanation: Liquids and gases can flow due to weaker intermolecular forces.
13. Which state of matter has the highest kinetic energy?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: d) Plasma
Explanation: Plasma particles have extremely high energy due to ionization.
14. The term ‘fluid’ is used for ________.
a) Solids
b) Liquids and gases
c) Gases only
d) Plasmas only
Answer: b) Liquids and gases
Explanation: Liquids and gases can flow, so they are called fluids.
15. The density of a substance is given by the formula:
a) Mass × Volume
b) Volume ÷ Mass
c) Mass ÷ Volume
d) Mass × Acceleration
Answer: c) Mass ÷ Volume
Explanation: Density is mass per unit volume.
16. Which state of matter is characterized by particles vibrating in place?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: a) Solid
Explanation: In solids, particles vibrate about fixed positions.
17. Which of the following expands the most on heating?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: c) Gas
Explanation: Gases expand the most due to weak intermolecular forces.
18. What is diffusion?
a) Movement of solids
b) Mixing of particles due to motion
c) Liquid to gas conversion
d) Gas to liquid conversion
Answer: b) Mixing of particles due to motion
Explanation: Diffusion occurs due to random motion of particles.
19. Which state of matter is used in fluorescent lamps?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: d) Plasma
Explanation: Fluorescent lamps contain ionized gas (plasma).
20. Which state of matter is most incompressible?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: a) Solid
Explanation: Solid particles are tightly packed, so they cannot be compressed easily.
21. The process of conversion of liquid into gas at any temperature is called:
a) Boiling
b) Evaporation
c) Condensation
d) Freezing
Answer: b) Evaporation
Explanation: Evaporation occurs at all temperatures from the surface of a liquid.
22. Boiling occurs when:
a) Vapor pressure = Atmospheric pressure
b) Vapor pressure < Atmospheric pressure
c) Vapor pressure > Atmospheric pressure
d) Liquid is cooled
Answer: a) Vapor pressure = Atmospheric pressure
Explanation: At boiling point, vapor pressure equals atmospheric pressure.
23. Conversion of gas into liquid is called:
a) Evaporation
b) Condensation
c) Sublimation
d) Fusion
Answer: b) Condensation
Explanation: Condensation changes gas into liquid by cooling.
24. Conversion of liquid into solid is called:
a) Evaporation
b) Freezing
c) Melting
d) Sublimation
Answer: b) Freezing
Explanation: Freezing occurs when temperature is lowered below the freezing point.
25. Ice melts at:
a) 0°C
b) 100°C
c) 32°F
d) Both a and c
Answer: d) Both a and c
Explanation: Ice melts at 0°C (32°F) under normal atmospheric pressure.
26. The heat required to convert solid to liquid at constant temperature is called:
a) Latent heat of vaporization
b) Latent heat of fusion
c) Specific heat
d) Sensible heat
Answer: b) Latent heat of fusion
Explanation: It’s the energy needed to change the phase from solid to liquid without temperature change.
27. Which factor increases the rate of evaporation?
a) Low temperature
b) Low surface area
c) High wind speed
d) High humidity
Answer: c) High wind speed
Explanation: Higher wind speed removes vapor molecules, increasing evaporation.
28. During boiling, temperature of a liquid:
a) Increases continuously
b) Decreases
c) Remains constant
d) First increases, then decreases
Answer: c) Remains constant
Explanation: All heat energy is used for phase change, not for raising temperature.
29. Dry ice is solid:
a) Water
b) Carbon dioxide
c) Nitrogen
d) Oxygen
Answer: b) Carbon dioxide
Explanation: Solid CO₂ sublimates directly into gas at normal pressure.
30. Which process is reverse of sublimation?
a) Evaporation
b) Deposition
c) Condensation
d) Fusion
Answer: b) Deposition
Explanation: Deposition changes gas directly into solid.
31. Melting point of a solid depends on:
a) Atmospheric pressure
b) Intermolecular forces
c) Temperature only
d) Both a and b
Answer: d) Both a and b
Explanation: Stronger intermolecular forces and changes in pressure affect melting point.
32. Freezing point of a liquid decreases by:
a) Adding impurities
b) Increasing temperature
c) Increasing pressure
d) None of these
Answer: a) Adding impurities
Explanation: Impurities lower the freezing point (freezing point depression).
33. The temperature at which a substance changes from liquid to gas is called:
a) Freezing point
b) Boiling point
c) Melting point
d) Sublimation point
Answer: b) Boiling point
Explanation: Boiling point is when vapor pressure equals external pressure.
34. Latent heat of vaporization of water is:
a) 540 cal/g
b) 80 cal/g
c) 4200 J/kg
d) 100 cal/g
Answer: a) 540 cal/g
Explanation: It’s the energy required to convert water into vapor at constant temperature.
35. Evaporation causes cooling because:
a) Molecules gain energy
b) Molecules lose high-energy particles
c) Pressure increases
d) Temperature increases
Answer: b) Molecules lose high-energy particles
Explanation: High-energy molecules escape, lowering average kinetic energy.
36. The temperature at which solid, liquid, and gas coexist is called:
a) Boiling point
b) Triple point
c) Critical point
d) Sublimation point
Answer: b) Triple point
Explanation: Triple point is a unique temperature and pressure for coexistence of all three states.
37. Water boils at lower temperature on mountains because:
a) Pressure is higher
b) Pressure is lower
c) Gravity is less
d) Temperature is lower
Answer: b) Pressure is lower
Explanation: Lower atmospheric pressure reduces boiling point.
38. Conversion of vapor into ice directly is called:
a) Condensation
b) Freezing
c) Deposition
d) Sublimation
Answer: c) Deposition
Explanation: Deposition changes gas directly into solid.
39. Which process is used in making ice-cream without a freezer?
a) Using cold water
b) Adding salt to ice
c) Adding sugar to ice
d) Using hot water
Answer: b) Adding salt to ice
Explanation: Salt lowers freezing point, allowing ice to absorb more heat.
40. Which change of state absorbs heat?
a) Freezing
b) Condensation
c) Melting
d) Deposition
Answer: c) Melting
Explanation: Melting absorbs heat to break bonds between particles.
41. Boyle’s law states that at constant temperature:
a) P ∝ V
b) P ∝ 1/V
c) V ∝ T
d) P ∝ T
Answer: b) P ∝ 1/V
Explanation: Boyle’s law: Pressure is inversely proportional to volume at constant temperature.
42. Charles’s law states that at constant pressure:
a) V ∝ T
b) V ∝ 1/T
c) P ∝ T
d) P ∝ 1/T
Answer: a) V ∝ T
Explanation: Volume of a gas increases with temperature at constant pressure.
43. Kelvin temperature scale starts from:
a) -273°C
b) 0°C
c) -273 K
d) 273°C
Answer: a) -273°C
Explanation: Absolute zero (-273°C) is 0 K.
44. Ideal gas equation is:
a) PV = nRT
b) PV = RT
c) P/T = V
d) PV/T = R
Answer: a) PV = nRT
Explanation: Ideal gas equation combines Boyle’s, Charles’s, and Avogadro’s laws.
45. Avogadro’s law states that equal volumes of gases contain:
a) Equal masses
b) Equal number of molecules
c) Equal density
d) Equal pressure
Answer: b) Equal number of molecules
Explanation: At same temperature and pressure, equal volumes contain equal molecules.
46. Gas pressure is due to:
a) Weight of gas
b) Collisions of molecules with container walls
c) Volume of container
d) Shape of container
Answer: b) Collisions of molecules with container walls
Explanation: Molecular collisions cause gas pressure.
47. If temperature is constant and volume is halved, pressure will:
a) Halve
b) Double
c) Remain same
d) Become zero
Answer: b) Double
Explanation: Boyle’s law: P₁V₁ = P₂V₂.
48. Charles’s law shows relation between:
a) Pressure and volume
b) Volume and temperature
c) Pressure and temperature
d) Volume and mass
Answer: b) Volume and temperature
Explanation: V/T = constant at constant pressure.
49. Pressure is measured in:
a) Pascal
b) Kelvin
c) Joule
d) Newton
Answer: a) Pascal
Explanation: Pascal (Pa) is the SI unit of pressure.
50. Temperature in gas laws must be measured in:
a) Celsius
b) Fahrenheit
c) Kelvin
d) Rankine
Answer: c) Kelvin
Explanation: Kelvin ensures proportionality in gas laws.
51. Gay-Lussac’s law relates:
a) Volume and temperature
b) Pressure and temperature
c) Pressure and volume
d) Temperature and density
Answer: b) Pressure and temperature
Explanation: P/T = constant at constant volume.
52. In the ideal gas equation PV = nRT, R is:
a) Gas constant
b) Resistance
c) Radius
d) Reactivity
Answer: a) Gas constant
Explanation: R = 8.314 J/mol·K.
53. At constant temperature, doubling volume will:
a) Double pressure
b) Halve pressure
c) Keep pressure constant
d) Increase temperature
Answer: b) Halve pressure
Explanation: Boyle’s law.
54. A gas expands when heated because:
a) Molecules become lighter
b) Kinetic energy increases
c) Pressure decreases
d) Molecules disappear
Answer: b) Kinetic energy increases
Explanation: Heating increases molecular motion, increasing volume.
55. Standard temperature and pressure (STP) is:
a) 0°C, 1 atm
b) 25°C, 1 atm
c) 0°C, 760 mmHg
d) Both a and c
Answer: d) Both a and c
Explanation: STP is 0°C and 1 atm (760 mmHg).
56. Which law is used in scuba diving gas calculations?
a) Boyle’s law
b) Charles’s law
c) Gay-Lussac’s law
d) Avogadro’s law
Answer: a) Boyle’s law
Explanation: Pressure-volume changes under water follow Boyle’s law.
57. The total pressure of a gas mixture equals sum of partial pressures is:
a) Dalton’s law
b) Avogadro’s law
c) Boyle’s law
d) Charles’s law
Answer: a) Dalton’s law
Explanation: Dalton’s law of partial pressures.
58. If gas temperature increases, volume increases at constant pressure due to:
a) Boyle’s law
b) Charles’s law
c) Avogadro’s law
d) Graham’s law
Answer: b) Charles’s law
Explanation: Volume is directly proportional to temperature.
59. Which gas law explains why balloons burst in sunlight?
a) Boyle’s law
b) Charles’s law
c) Avogadro’s law
d) Dalton’s law
Answer: b) Charles’s law
Explanation: Heat increases gas volume, causing burst.
60. Graham’s law relates to:
a) Diffusion of gases
b) Pressure
c) Volume
d) Temperature
Answer: a) Diffusion of gases
Explanation: Rate of diffusion ∝ 1/√molar mass.
61. Plasma is formed when:
a) Solid melts
b) Gas ionizes
c) Liquid freezes
d) Gas condenses
Answer: b) Gas ionizes
Explanation: Plasma is ionized gas.
62. Which state of matter is found in stars?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: d) Plasma
Explanation: Stars are mostly plasma.
63. Bose-Einstein condensate occurs at:
a) Very high temperature
b) Near absolute zero
c) Normal room temperature
d) In vacuum
Answer: b) Near absolute zero
Explanation: BEC forms at extremely low temperatures.
64. Which property distinguishes plasma from gas?
a) Fixed shape
b) Ionization
c) Strong bonds
d) Low density
Answer: b) Ionization
Explanation: Plasma has free ions and electrons.
65. Which state of matter conducts electricity best?
a) Solid metals
b) Liquids
c) Gases
d) Plasma
Answer: d) Plasma
Explanation: Free charged particles conduct electricity well.
66. Which is the fourth state of matter?
a) Liquid
b) Plasma
c) BEC
d) Gas
Answer: b) Plasma
Explanation: Plasma is called the fourth state.
67. Which state is sometimes called “superfluid”?
a) Plasma
b) Bose-Einstein condensate
c) Liquid helium
d) Both b and c
Answer: d) Both b and c
Explanation: BEC and liquid helium show superfluidity.
68. Which state is used in neon signs?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: d) Plasma
Explanation: Neon gas glows when ionized.
69. Superconductivity occurs in some materials when:
a) Heated
b) Cooled to low temperature
c) Compressed
d) Ionized
Answer: b) Cooled to low temperature
Explanation: Resistance drops to zero at low temperature.
70. Matter can change state by altering:
a) Temperature
b) Pressure
c) Both a and b
d) Neither a nor b
Answer: c) Both a and b
Explanation: Changes in temperature or pressure cause state change.
71. Which state has particles in fixed positions but can vibrate?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: a) Solid
Explanation: Solid particles vibrate about fixed points.
72. Which state has no fixed volume?
a) Solid
b) Liquid
c) Gas
d) Both b and c
Answer: c) Gas
Explanation: Gases have no fixed shape or volume.
73. Which property increases from solid → liquid → gas?
a) Density
b) Kinetic energy
c) Intermolecular force
d) Rigidity
Answer: b) Kinetic energy
Explanation: Particle motion increases.
74. Which state of matter has the strongest intermolecular forces?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: a) Solid
Explanation: Particles are tightly bound.
75. Which change of state releases heat?
a) Melting
b) Vaporization
c) Condensation
d) Sublimation
Answer: c) Condensation
Explanation: Gas to liquid releases latent heat.
76. Which change of state is endothermic?
a) Freezing
b) Condensation
c) Melting
d) Deposition
Answer: c) Melting
Explanation: Heat is absorbed to break bonds.
77. Which gas law explains LPG cylinder pressure?
a) Boyle’s law
b) Charles’s law
c) Gay-Lussac’s law
d) Dalton’s law
Answer: a) Boyle’s law
Explanation: Pressure varies inversely with volume.
78. At absolute zero, the motion of particles:
a) Stops completely
b) Increases
c) Becomes random
d) Doubles
Answer: a) Stops completely
Explanation: No kinetic energy at 0 K.
79. Critical temperature is:
a) Temp. above which gas cannot liquefy
b) Temp. below freezing point
c) Temp. of triple point
d) Temp. at 0 K
Answer: a) Temp. above which gas cannot liquefy
Explanation: Beyond critical temp, gas remains gas.
80. In diffusion, lighter gases diffuse:
a) Slower
b) Faster
c) Same rate as heavy gases
d) Not at all
Answer: b) Faster
Explanation: Graham’s law: rate ∝ 1/√molar mass.
81. Which is a man-made state of matter?
a) Solid
b) Plasma
c) BEC
d) Both b and c
Answer: d) Both b and c
Explanation: Plasma and BEC are created under special conditions.
82. Which state shows Brownian motion?
a) Solid only
b) Liquid only
c) Gas only
d) Both liquids and gases
Answer: d) Both liquids and gases
Explanation: Brownian motion occurs in fluids.
83. Which change of state is used in refrigerators?
a) Evaporation and condensation
b) Sublimation
c) Melting
d) Deposition
Answer: a) Evaporation and condensation
Explanation: Refrigeration cycles use phase changes to absorb and release heat.
84. Which type of solid has no definite melting point?
a) Crystalline
b) Amorphous
c) Ionic
d) Metallic
Answer: b) Amorphous
Explanation: Amorphous solids soften over a range of temperatures.
85. Glass is an example of:
a) Crystalline solid
b) Amorphous solid
c) Liquid
d) Gas
Answer: b) Amorphous solid
Explanation: Glass has disordered atomic arrangement.
86. Which state exists inside the sun?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: d) Plasma
Explanation: The sun is made of ionized gases.
87. Which is more compressible — liquid or solid?
a) Liquid
b) Solid
c) Same
d) None
Answer: a) Liquid
Explanation: Liquids have more space between particles than solids.
88. Which gas law is used in hot air balloons?
a) Boyle’s
b) Charles’s
c) Avogadro’s
d) Dalton’s
Answer: b) Charles’s
Explanation: Heating increases volume, making balloon rise.
89. Which state of matter has highest disorder?
a) Solid
b) Liquid
c) Gas
d) Plasma
Answer: c) Gas
Explanation: Gas particles move randomly in all directions.
90. Which of the following is an example of amorphous solid?
a) Diamond
b) Quartz
c) Glass
d) Sodium chloride
Answer: c) Glass
Explanation: Glass lacks a regular crystal structure, so it is amorphous.
91. Which state of matter is known as the fourth state of matter?
a) Gas
b) Plasma
c) Bose–Einstein condensate
d) Liquid
Answer: b) Plasma
Explanation: Plasma is called the fourth state of matter, consisting of ionized particles.
92. Which of the following processes is exothermic?
a) Melting of ice
b) Evaporation of water
c) Condensation of steam
d) Sublimation of camphor
Answer: c) Condensation of steam
Explanation: Condensation releases heat to the surroundings.
93. Which of the following is NOT a crystalline solid?
a) Sodium chloride
b) Quartz
c) Sugar
d) Rubber
Answer: d) Rubber
Explanation: Rubber is amorphous, not crystalline.
94. Which factor does NOT affect the rate of evaporation?
a) Surface area
b) Temperature
c) Humidity
d) Density of liquid
Answer: d) Density of liquid
Explanation: Evaporation rate is influenced mainly by temperature, surface area, and humidity.
95. Which of the following best describes sublimation?
a) Liquid → Gas
b) Solid → Gas
c) Gas → Liquid
d) Solid → Liquid
Answer: b) Solid → Gas
Explanation: Sublimation is the direct change from solid to gas without becoming liquid.
96. Which state of matter exists at very low temperatures and behaves as a single quantum entity?
a) Plasma
b) Bose–Einstein condensate
c) Liquid
d) Superfluid
Answer: b) Bose–Einstein condensate
Explanation: Bose–Einstein condensates occur near absolute zero with atoms behaving in unison.
97. Which is the slowest process among the following?
a) Diffusion in gases
b) Diffusion in liquids
c) Diffusion in solids
d) All are same
Answer: c) Diffusion in solids
Explanation: Particle motion is slowest in solids, so diffusion is very slow.
98. Which type of change is melting of ice?
a) Physical change
b) Chemical change
c) Both a and b
d) Neither a nor b
Answer: a) Physical change
Explanation: Melting of ice changes state but not chemical composition.
99. What happens to the kinetic energy of particles when a solid changes into liquid?
a) Decreases
b) Increases
c) Remains same
d) First decreases then increases
Answer: b) Increases
Explanation: Particle movement increases during melting, so kinetic energy increases.
100. Which gas law explains why a balloon expands when heated?
a) Boyle’s law
b) Charles’s law
c) Avogadro’s law
d) Dalton’s law
Answer: b) Charles’s law
Explanation: Charles’s law states that at constant pressure, volume of a gas is directly proportional to temperature.