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 physics the kinetic model of matter evaporation heat, internal energy and work phase change

When the temperature of water rises, the rate of evaporation decreases. State whether true or false.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The statement if False.
Actually, rate of evaporation of a liquid decreases as the temperature decreases. As intermolecular force increase rate of evaporation decreases. This happens because intermolecular force make it less likely for the molecules on the surface to escape from liquid and become vapour gas. As temperature increases rate of evaporation increases.
Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

Why mercury do not evaporate at room temperature?

  1. Because melting point of mercury is higher

  2. Because boiling point of mercury is higher

  3. Because boiling point of mercury is lower

  4. Because boiling point of mercury is equal to room temperature
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Evaporation is a process in which some molecules of a liquid, which have greater kinetic energy, escape from the liquid and enter the atmosphere.

When the temperature of the liquid is closer to its boiling point, greater is the evaporation. 
Besides the boiling point being higher, the cohesive force of attraction among the molecules of mercury is greater than other liquids like water. This further reduces the evaporation rate.

Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

Evaporation is the process of changing liquid into vapour below its boiling point. State whether true or false.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Evaporation is the process of changing liquid into vapour below B.P. (boiling point)
It is the type of vaporisation that occurs on the surface of liquid due to increase in temperature or pressure it changes liquid into gaseous phase before reaching to B.P. The surrounding gas must not be saturated by evaporating substance.
Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

The molecules of liquid change into vapour when the pressure of molecules of liquid

  1. exceeds the atmospheric pressure

  2. becomes less than the atmospheric pressure

  3. becomes equal to the atmospheric pressure

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

When the pressure of molecules of liquid become equal to the atmospheric pressure, the molecules of liquid change into vapours.

Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

Water in an earthen pitcher gets cooled due to

  1. slower rate of evaporation

  2. faster rate of evaporation

  3. no evaporation at all

  4. some unknown reason
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Earthen pots are used in summer. The pot has several pores through which water rinses out to the outer surface of the earthen pot and evaporates. In this process it takes away heat from the water inside the pitcher. As a result, the water inside gets cooled.

Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

What is not true about evaporation?

  1. Greater the surface area of the liquid, the quicker is the evaporation

  2. Evaporation produces cooling

  3. Evaporation takes place at all the temperatures

  4. Evaporation is nothing but boiling at the highest temperature of the liquid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Evaporization is the vaporization process of converting the liquid phase to vapour phase when surrounding temperature is more than liquid / water temperature.

It should not be confused with boiling as boiling means whole phase change from liquid to vapour at highest temperature.

Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

Statement-1
Evaporation takes place from the surface of a liquid.
Statement-2
The molecules at the surface have less attractive energy than those inside the liquid.

  1. Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation for Statement- 1

  2. Statement-1 is true, Statement-2 is true but Statement-2 is not the correct explanation for Staement-1

  3. Statement-1 is true, Statement-2 is false.

  4. Statement-1 is false, Statement-2 is true.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Evaporation is a surface phenomenon.
Particles present on the surface of a liquid only face attraction from one side (the side containing fluid particles) and surface tension. Where as particles inside the liquid would face attractive forces from all around, making it difficult for such particles to evaporate or escape.
Hence the statement is true, explanation is true and the explanation is the correct explanation for the statement.

Multiple choice physics the kinetic model of matter evaporation heat, internal energy and work phase change

Which of the following statement is wrong ?

  1. At room temperature evaporation of water is rapid as compared to ethanol

  2. Water is more viscous as compared to ethanol

  3. Liquid drops are spherical in shape

  4. Clothes are easily dried in dry day as compared to humid days
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

A: At room temperature evaporation of ethanol is rapid as compared to water. Hence, A is incorrect. 

B: water is more viscous compared to ethanol, hence statement is true. 
C: liquid drops are spherical due to surface tension of liquid drop,hence statement is true.
D: Clothes are dried easily as it is less humid on dry day,hence statement is true. 

Multiple choice chemistry hydroxy compounds and ethers physical properties of ethers ethers alcohols, phenols and ethers

Which of the following is true regarding density?

  1. Diethyl ether has higher density than water.

  2. Diethyl ether has lower density than water.

  3. Diethyl ether is as dense as water.

  4. The density of diethyl ether depends on its method of preparation.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Diethyl ether has lower density than water. The density of diethyl ether is 713 kg/m$^3$. The density of water is 1000 kg/m$^3$.
Water molecules are closer to each other than the molecules of ether. This is due to intermolecular hydrogen bonding in water which is not possible in diethyl ether.