Thermal Equilibrium

Q.

Two factors on which the heat absorbed or given out by a body depends are

1. Mass and Temperature

2. Mass and specific heat capacity of the body

3. Temperature and specific heat capacity of the body

4. Temperature and heat capacity of the body

Q. What is the name given to the energy absorbed during a phase change?

Q.

To what temperature must a gas at $300\mathrm{K}$ be cooled in order to reduce its volume to 1/3rd of its original volume, pressure remaining constant?

Q.

The temperature of a body depends on the ___ contained in it.

Q.

A piece of ice is heated at a constant rate. The variation of temperature with heat input is shown in the graph:

AB and CD represent:

1. AB represents melting of ice and CD represents boiling of water

2. AB represents melting of ice and CD represents heating of water

3. AB represents heating of ice and CD represents heating of water

4. AB represents heating of water and CD represents boiling of water

Q.

Heat and temperature can be respectively defined as

1. Form of energy that gives the sensation of hotness or coldness of a body and ability to hold heat

2. Measure of Temperature and measure of hotness or coldness of a body

3. Form of energy that gives the sensation of hotness or coldness of a body and measure of hotness or coldness of a body

4. Measure of Temperature and ability to hold heat

Q.

When two bodies A and B are brought in contact with each other, heat does not flow between them. When another body C is brought in contact with B, the heat starts flowing from C to B. After the heat flow stops, C is now brought into contact with A, then which of the following is correct?

1. No heat flows between A and C.

2. Heat flows from C to A.

3. Heat flows from A to C.

4. Heat first flows from A to C and then from C to A.

Q. A beaker contains 40g of water at 20?C. Now 50g of ice is put into the beaker . What is the final temperature of the mixture?

Q.

State True or False:

If 2 bodies, A and B are in thermal equilibrium, and B and another body D are in thermal equilibrium, then A and D are also in thermal equilibrium

1. True

2. False

Q.

The Principle of CALORIMETRY or MIXTURES states that when a hot body comes in contact with a cold body :

1. The heat lost by the hot body is equal to that gained by the cold body till they possess equal amount of heat

2. The heat lost by the hot body is equal to that gained by the cold body till they achieve a state of thermal equilibrium

3. The heat lost by the hot body is equal to that gained by the cold body till they achieve a state of mechanical equilibrium

4. The temperature lost by the hot body is equal to that gained by the cold body till they achieve a state of mechanical equilibrium

5. The temperature lost by the hot body is equal to that gained by the cold body till they achieve a state of thermal equilibrium

Q. Heat flows from one body to another if there is a difference in between the two bodies.

1. temperature
2. mass
3. height

Q.

Which of the given statements is true regarding a hot and cold body?

1. The hot body will still remain slightly hot even after attaining thermal equilibrium.

2. The cold body will become hotter than the hot body after attaining thermal equilibrium.

3. The heat loss by the hot body will be equal to the heat gained by the cold body.

4. None of the above

Q. Two bodies are brought in contact with each other. If heat flows from A to B, then in comparison with the other body, .

1. A is hotter
2. B is hotter
3. A is colder

Q. If two bodies A and B are at room temperature, then _________.

1. heat flows from A to B
2. heat flows from B to A
3. heat is absorbed by surroundings
4. no heat flow happens

Q. For the given endothermic reaction,

1. $P-3,Q-4,R-1,S-2$
2. $P-4,Q-2,R-3,S-1$
3. $P-1,Q-2,R-4,S-3$
4. $P-3,Q-1,R-2,S-4$

Q. The temperature increases is not notices in which of the following processed on providing heat to system?
(I) Fusion at melting point
(II) Phase transition at transition temperature
(III) Boiling at boiling point
(IV) A reaction in chemical equilibrium

1. I, III
2. III, IV
3. II, IV
4. I, II, III

Q.

Two bodies are said to be in thermal equilibrium if they have equal

1. temperature
2. heat energy
3. mechanical energy

Q. $5g$ of water at ${30}^{\circ }C$ and $5g$ of ice at $-{20}^{\circ }C$ are mixed together in a calorimeter. Find the final temperature of the mixture. Assume water equivalent of calorimeter to be negligible, specific heats of ice and water are $0.5$ and $1cal/g^{\circ }C$, and latent heat of ice is $80cal/g$.

1. $0^{\circ }C$
2. ${10}^{\circ }C$
3. $-{30}^{\circ }C$
4. $>{10}^{\circ }C$

Q. What happens on thermal decomposition of $Ba(N_3{)}_2$? (write only equation of the reaction).

Q. Figure shows two flasks connected to each other. The volume of the flask 1 is twice that of flask 2. The system is filled with an ideal gas at temperature 100 K and 200 K respectively in the flasks. If the mass of the gas in 1 m, then what is the mass of the gas in flask 2 in equilibrium?

1. $m$
2. $\frac{m}{4}$
3. $\frac{m}{8}$
4. $\frac{m}{2}$

Q. A gas in container A is in thermal equilibrium with another gas of the same mass in container B. If we denote the corresponding pressure and volume of the suffixes A and B, then which of the following statements is most likely to be true?

1. $P_A$ $\ne$ $P_B$, $V_A=V_B$
2. $P_A=P_B$, $V_A$ $\ne$ $V_B$
3. $\frac{P_A}{V_A}$ = $\frac{P_B}{V_B}$
4. $P_A{V}_A$ = $P_B{V}_B$

Q. The initial temperatures of two bodies B and C were $T_1$ and $T_2$ respectively. They are brought into contact and heat starts flowing from C to B until their temperature reaches $T$. Which of the following is true?

1. $T_1<T<T_2$
2. $T<T_1<T_2$
3. $T_2<T<T_1$
4. $T_2<T_1<T$

Q. Two bodies A, B and bodies B, C are in thermal equilibrium with each other. If the temperature of A and B is ${45}^{\circ }\text{C}$, then the temperature of C is ${45}^{\circ }\text{C}$. Explain.

Q. Assertion :Two bodies at thermal equilibrium may or may not have equal heat. Reason: Two bodies at thermal equilibrium have same temperature.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q. The initial temperatures of two bodies B and C were ${\text{T}}_1$ and ${\text{T}}_2$ respectively. Now, they are brought into contact and heat starts flowing from C to B until their temperature reaches $\text{T}$, then which of the following are true?

1. $\text{T}>{\text{T}}_1$
2. $\text{T}<{\text{T}}_2$
3. $\text{T}<{\text{T}}_1$
4. $\text{T}>{\text{T}}_2$

Q. $C{H}_4\left(g\right)+2O_2\left(g\right)\to C{O}_2\left(g\right)+2H_{2}O\left(g\right)+800kJ$. If a mole of $O_2\left(g\right)$ is consumed in the reaction, what energy is produced?

1. $200kJ$
2. $400kJ$
3. $800kJ$
4. $1200kJ$
5. $1600kJ$

Q.

45g of water at 50C in a beaker is cooled when 50g of copper at 18C is added to it. The contents are stirred till a final constant temperature is reached. calculate this final temperature. the specific heat capacity of copper is 0.39J/g/K and that of water is 4.2J/g/K.

Q. The increase of pressure on ice $\rightleftharpoons$ water system at constant temperature will lead to:

1. no effect on the equilibrium
2. an increase in the Gibbs energy of the system
3. a shift of the equilibrium in the forward direction
4. a decrease in the entropy of the sysytem

Q. Heats of neutralization $\left(△H\right)$ of $N{H}_{4}OH$ and $HF$ are $-51.5$ and $68.6kJ$ respectively. Calculate their heats of dissociation.

Q. The equilibrium between gaseous isomers A, B and C can be represented as:
$A\left(g\right)\leftrightharpoons B\left(g\right);K_1=?$
$B\left(g\right)\leftrightharpoons C\left(g\right);K_2=0.4$
$C\left(g\right)\leftrightharpoons A\left(g\right);K_3=0.6$
If one mole of A is taken in closed vessel of volume 1 L, then

1. [A] + [B] + [C] = 1 M at amy moment of reaction.
2. Concentration of C is 1.2 M at equilibrium
3. The value of $K_1$ is 1/0.24
4. Isomer A is thermodynamically least stable