______ separates the system from the surroundings.

Which of the following is an extensive property of a system?

1. Temperature
2. Pressure
3. Number of moles
4. Density

What are the particles of the system (red-hot iron rod) shown below?

1. Iron molecules
2. Iron atoms
3. Copper atoms
4. Brass atoms

Which of the following cannot be a heat reservoir?

1. Air
2. Stove top
3. Sea
4. Earth

During a thermodynamic process, 30 joules of heat are added to a gas while 25 joules of work are done by the gas. The change in internal energy of a system is ____ J.

During an isothermal process 125 J of heat are removed from a trapped gas. Find out the change in internal energy of the system.

In an isothermal process the change in internal energy of the system is ____.

During a thermodynamic process, 438 J of heat is removed from a gas system while 238 J of work is done on the gas. The change in internal energy of a system is _____ J.

1. 200
2. - 200
3. - 676
4. 676

A cold reservoir is touched to a system, which of the following may happen?

1. The heat flows from the system to the reservoir
2. The internal energy of the system decreases
3. The temperature of the system decreases
4. All of the above

When there is no heat exchange between the system and the reservoir, ____.

1. The system is said to have enough heat
2. The reservoir is said to have enough heat
3. The system and the reservoir are said to be in thermal equilibrium
4. The system is not connected to the reservoir

The internal energy of a system does not change in a/an _____ process.
(A) Isothermal
(B)  Adiabatic
(C)  Isochoric
(D)   Isobaric

1. A and C
2. A and B
3. B and D
4. All of them

Energy can be added to a system by ____.

1. Work
2. Heat
3. Both a and b
4. None

Internal energy denotes ______.

1. Kinetic energy
2. Potential energy
3. Electrostatic energy
4. Sum of all of the above

When the pressure inside the system is smaller than the pressure outside it, the work is done ______.

1. By the system
2. On the system
3. On the surrounding
4. All of the above

During a thermodynamic process, 540 J of heat is removed from a gas system while 1200 J of work done on the gas. The change in internal energy of a system is _______J.

During a thermodynamic process, 230 joules of heat are added to a gas while 200 joules of work are done by the gas. The change in internal energy of a system is ______ J.