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

What would happen if a solid substance is heated for a while?

  1. Kinetic energy among the particles will decrease.

  2. The particles will show vibratory motion.

  3. The intermolecular bonds among the particles will get strengthened.

  4. The forces of attraction among the particles will increase.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

On increasing the temperature of solids, the kinetic energy of the particles increases. Due to the increase in kinetic energy, the particles start vibrating with greater speed. The energy supplied by heat overcomes the forces of attraction between the particles. The particles leave their fixed positions and start moving more freely. A stage is reached when the solid melts and is converted into a liquid.

Multiple choice

Why is salt is used to melt ice?

  1. To lower the freezing point of water.

  2. To increase the melting point of water.

  3. Both (1) and (2)

  4. To produce the heat by decomposition of salt molecules.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Salt acts as anti-freeze. Water becomes ice at a temperature of 32 degrees Fahrenheit (0 degrees Celsius) and adding salt to water lowers the freezing point, thus preventing the formation of ice.

Multiple choice

Consider the following statements:

  1. Due to high heat capacity of clinical thermometer, it measures change in body temperature.
  2. Leaching is the process of extracting minerals from a solid by dissolving them in a liquid.

Which of the given statements is/are correct?

  1. Only (1)

  2. Only (2)

  3. Both (1) and (2)

  4. Neither (1) nor (2)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Statement (1) is wrong. Clinical thermometer has low heat capacity, i.e. mercury (present in thermometer) has less specific heat to warm up. Therefore, thermometer measures even the small change in body temperature. Statement (2) is correct. Yes, leaching is the process of extracting minerals from a solid by dissolving them in a liquid. Uranium and gold are extracted from their ores by chemical leaching.

Multiple choice

If some droplets of water are poured into a pan of boiling vegetable oil, something is spilt out. Which of the following statements is/are correct? (1) The boiling point of oil is lower than the boiling of water. (2) The vapour of oil spills out the droplets of water. (3) The drop of water vaporizes in the pan of oil and spills out some oil.

  1. Only (1)

  2. Only (3)

  3. Only (1) and (2)

  4. Only (1) and (3)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Statement (1) is incorrect. The boiling point of vegetable oil is high as compared to that of water. Statement (2) is incorrect. As boiling point of water is low, it changes into water vapours and increases the density of oil. Statement (3) is correct. The water droplets vaporise and leave the oil behind in the pan.

Multiple choice

Some vegetables are to be cooked in a pressure cooker. At which of the following places will the cooking process take the longest time?

  1. Shimla

  2. Jaipur

  3. Bangalore

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

At higher altitudes, the atmospheric pressure decreases. Atmospheric pressure exerts pressure on the molecules of the liquid, confining them. In order to boil, the electrons must be excited, but must become hotter to overcome the pressure of the atmosphere. Therefore, pressure makes a liquid boil at a higher temperature. At Shimla, water actually boils at a faster rate, but it takes longer to cook vegetables. So, it is recommended to add salt in water, which decreases the boiling point of water, to cook the vegetables.

Multiple choice

Which of the following statements about solid carbon dioxide is/are correct?

  1. It is used in theatres to give special effects.
  2. It is extremely a cold substance.
  3. It is used to freeze food and to keep ice-cream cold.

  1. Only 1

  2. Only 2

  3. Only 1 and 2

  4. All 1, 2 and 3
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Statement (1) is correct. Solid carbon dioxide is used in theaters to give special effects.

Statement (2) is correct. Solid carbon dioxide or dry ice is extremely cold. Its approx. temperature is -109.3°F or -78.5°C. Statement (3) is correct. Solid carbon dioxide is used to freeze food and to keep ice cream cold because of its existence in extremely low temperature.

Multiple choice

Consider the following statements:

  1. When an open bottle of scent is kept in a corner of the room, its fragrance can be sensed in the entire room. This is due to the phenomenon of diffusion.
  2. When a solid is changed to gas without melting, the process is called vapourisation.

Which of the given statements is/are correct?

  1. Only (1)

  2. Only (2)

  3. Both (1) and (2)

  4. Neither (1) nor (2)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Statement (1) is correct. When an open bottle of scent is kept in a corner of the room, its odour is felt in all the corners. This is due to the phenomenon of diffusion. The movement of particles from its higher concentration to its lower concentration is called diffusion. Statement (2) is incorrect. Sublimation is the transition of a substance directly from the solid phase to the gas phase without passing through an intermediate liquid phase.