Chemistry · Science General

States of Matter

2,682 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

Which liquid is used in a laboratory thermometer?

  1. Alcohol

  2. Water

  3. Ether

  4. Mercury

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

Mercury is the standard liquid used in laboratory thermometers due to its uniform thermal expansion, high boiling point (357°C), and low freezing point (-39°C). It doesn't wet glass, making it easy to read. Alcohol is sometimes used in low-temperature thermometers, but mercury remains the preferred choice for most laboratory applications.

Multiple choice

Shweta has opened a water tap and is trying to break the stream of water with her fingers. Why is she unable to cut the stream of water?

  1. Because matter is made up of particles

  2. Because particles of matter are continuously moving

  3. Because particles of matter attract each other

  4. Because particles of matter have small spaces between them
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The above activity suggests that particles of matter have force acting between them. This force keeps the particles together.

Multiple choice

While boiling a liquid, Siya noticed that the temperature remains constant during the change of state. What is the possible reason for this?

  1. The extra heat is used to break the bonds among the particles.

  2. The extra energy is used by the container.

  3. The extra energy is lost in the atmosphere.

  4. The extra energy is used to decrease the kinetic energy among the particles.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For any substance, the temperature remains constant during the change of state as the extra heat is absorbed by the particles to break the bonds between them.

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

Which of the following is not a characteristic of Green Solvents?

  1. They are non-Halogenated

  2. Boiling point is less than or equal to 200 degree Celsius

  3. They are biodegradable, stable and recyclable

  4. They are highly water soluble
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct as green solvents have low water solubility (<5 wt% in solvent).

Multiple choice

The reason to add coolant in a motor engine is to

  1. increase the acceleration

  2. reduce the volume of harmful exhaustible gases

  3. to lower the temperature of the engine

  4. to increase the lubrication of piston of the engine
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Coolant is a fluid, which flows through the engine to prevent its overheating. It is also called ‘anti-freeze’, which keeps the water that cools the engine from freezing.

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.