Home
Class 12
CHEMISTRY
A liquid is in equilibrium with its vapo...

A liquid is in equilibrium with its vapours at its boiling point. On the average, the molecules in the two phases have euqal :

A

intermolecular forces

B

potential energy

C

total energy

D

kinetic energy

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the properties of a liquid and its vapor at the boiling point, where they are in equilibrium. The question asks what the average molecules in both phases have equal values of. ### Step-by-Step Solution: 1. **Understanding the Concept of Equilibrium**: At the boiling point, a liquid is in equilibrium with its vapor. This means that the rate of evaporation of the liquid equals the rate of condensation of the vapor. 2. **Analyzing Intermolecular Forces**: In liquids, the intermolecular forces are stronger than in gases. This is because the molecules in a liquid are closer together compared to those in a vapor. Therefore, the average intermolecular forces in the liquid and vapor phases are not equal. 3. **Considering Potential Energy**: The potential energy of molecules in a gas is generally higher than that in a liquid due to the greater distances between gas molecules and the weaker intermolecular attractions. Hence, potential energy is not equal in both phases. 4. **Evaluating Total Energy**: Total energy is the sum of kinetic energy and potential energy. Since potential energy differs between the two phases, the total energy will also differ. Thus, total energy cannot be equal in both phases. 5. **Examining Kinetic Energy**: Kinetic energy is given by the formula \( KE = \frac{3}{2}RT \) for ideal gases, where \( R \) is the gas constant and \( T \) is the temperature. At the boiling point, both the liquid and vapor are at the same temperature. Therefore, the average kinetic energy of the molecules in the liquid phase is equal to that in the vapor phase. 6. **Conclusion**: Since the only property that is equal on average for the molecules in both phases at the boiling point is kinetic energy, we conclude that: **The average kinetic energy of the molecules in the liquid and vapor phases is equal.** ### Final Answer: The average kinetic energy of the molecules in the two phases is equal. ---
Promotional Banner

Similar Questions

Explore conceptually related problems

A liquid is in equilibrium with its vapour at its boiling point. On the average, the molecules in the two phases have equal: 1)potential energy 2)total energy 3)kinetic energy 4)intermolecular forces.

A liquid is in equilibrium with its vapour at its boiling point. On average, the molecules in the two phases have equal

A liquid is in equilibrium with its vapour at its boiling point. On average, the molecules in the two phases have equal

A liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased. a. what is the initial effect of the change on vapour pressure? b. How do rates of evaporation and condensation change initially? c. What happens when equilibrium is restored finally and what will be the final vapour pressure?

When an ideal binary solution is in equilibrium with its vapour, molar ratio of the two components in the solution and in the vapur phase is :

In liquid gas equilibrium, the pressure of vapours above the liquid is constant at

The surface tension of liuid at its boiling point

A liquid is in equilibrium with its vapour at a certain temperature. If DeltaH_(vap) = 60.24 kJ mol^-1 and DeltaS_(vap) = 150.6 J mol^-1 then the boiling point of the liquid will be

The average velocity of the molecules in a gas in equilibrium is

A cylinder fitted with movable piston contains liquid water in equilibrium with water vapour at 25°C. Which operation would result in a increase in the equilibrium vapour pressure.