Chemistry · Science General

States of Matter

2,382 Questions

States of matter questions explore physical changes, evaporation, phase transitions, and the properties of liquids and gases. Topics cover density, cryosurgery, heavy water, and electrolytes. This foundational chemistry topic frequently appears in general science sections of SSC and railway exams.

Phase change mechanismsEvaporation and temperature effectsProperties of liquidsPhysical versus chemical changesElectrolytes and heavy water

States of Matter Questions

Multiple choice

Why does the water in an earthen pot cool in summer?

  1. It is due to the phenomenon of vapourisation.

  2. It is due to the phenomenon of evaporation. The water seeps through the pores in the pot and evaporates.

  3. The mud is bad conductor of heat.

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Earthen pots have microscopic pores through which water seeps and evaporates from the outer surface. Evaporation requires latent heat of vaporization, which is drawn from the water inside the pot, cooling it down. This is an effective natural cooling method.

Multiple choice

The temperature at and above which vapour of a substance cannot be liquified is called _____.

  1. critical temperature

  2. saturated temperature

  3. zero temperature

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

Critical temperature is the temperature above which a gas cannot be liquefied by applying pressure, no matter how high the pressure. Above this temperature, the substance exists only as a gas or supercritical fluid. This is a fundamental property of each substance.

Multiple choice

Viscosity of a fluid _____.

  1. increases as the temperature increases

  2. decreases as the temperature increases

  3. does not depend on temperature

  4. decreases with pressure
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice

Why is mercury preferred as a barometric liquid?

  1. It has minimum density.

  2. It has maximum density.

  3. It is an easily available liquid.

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

Mercury's very high density (13.6 g/cm³) allows for a reasonably short barometer column (~76 cm) to measure atmospheric pressure. Less dense fluids would require impractically tall columns (over 10 meters for water).

Multiple choice

Dry ice is composed of

  1. carbon dioxide

  2. hydrocarbon

  3. water

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

Dry ice is the solid form of carbon dioxide (CO₂). It's called 'dry' because it sublimates (transitions directly from solid to gas) without becoming liquid, unlike water ice. Options B, C, and D are incorrect - dry ice is not made of hydrocarbons, water, or chlorine.

Multiple choice

Which one of the following systems has maximum entropy?

  1. One mole of water vapour

  2. One mole of liquid water

  3. One mole of solid water

  4. One mole of water at triple point.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Entropy is a measure of disorder, and gases have the highest entropy among the three states of matter. Water vapour (gas) has maximum entropy compared to liquid water or solid water (ice). At the triple point, water exists in equilibrium between all three phases, giving it less entropy than pure vapour.

Multiple choice

Which process is involved in all the examples given below? a) Tea leaves give flavour to the water in which it is boiled. b) Spreading of garbage stink from the dustbin. c) Spreading of aroma of flowers. d) Spreading of blue colour of ink in a glass full of water.

  1. Mixing

  2. Sedimentation

  3. Diffusion

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

Yes, all are the examples of diffusion. It refers to the process by which molecules intermingle as a result of their kinetic energy of random motion.

Multiple choice

Which of the following is not an osmotic solution?

  1. Water

  2. Hypotonic solution

  3. Isotonic solution

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

Osmotic solutions can cause osmosis when seperated from water by semi-permeable membrane. Water acts as solvent. So, water is not an osmotic solution.

Multiple choice

Which of the following statements is incorrect about liquid SO2?

  1. SO2(liq) is used as a non-aqueous solvent.

  2. SO2(liq) is a good solvent for phosphorus, iodine, sulphur, etc.

  3. SO2(liq) is used in antirefrigerating agent.

  4. Both (1) and (2) are correct.

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct because sulphur dioxide liquid has a high latent heat of vapourisation and hence, is used as a refrigerating agent. 

Multiple choice

Match the following:

 
a. Evaporation 1. The process of changing of water vapours into the liquid state on cooling
b. Condensation 2. The process of converting a liquid into its vapours by heating it below the boiling point of the liquid
c. Crystallisation 3. The process of reappearance of excess of dissolved substance in hot water on cooling

  1. a - 3, b - 1, c - 2

  2. a - 1, b - 3, c - 2

  3. a - 1, b - 2, c - 3

  4. a - 2, b - 1, c - 3

  5. a - 2, b - 3, c - 1
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct option.