Test: Properties of Gasses & Gas Mixture - 2 - Mechanical Engineering MCQ

Assertion (A): A perfect gas is one that satisfies the equation of state and whose specific heats are constant.  

Reason (R): The enthalpy and internal energy of a perfect gas are functions of temperature only.

Consider an ideal gas contained in vessel. If intermolecular interaction suddenly begins to act, which of the following happens?

Consider the following statements:

A real gas obeys perfect gas law at a very

1. High temperature

2. High-pressure

3. Low pressure

Which of the following statements is/are correct?

If a real gas obeys the Clausius equation of state p(v – b) = RT then,

Reduced pressure is

The internal energy of a gas obeying Van der Waal‟s equation 

Which one of the following statements is correct?

The value of compressibility factor for an ideal gas may be:

1. less or more than one

2. equal to one      

3. zero 4. less than zero

The correct value(s) is/are given by:

Assertion (A): An adiabatic process is always a constant entropy process.

Reason(R): In an adiabatic process there is no heat transfer.

In which of the following processes, the heat is fully converted into work?

An ideal gas undergoes an isothermal expansion from state R to state S in a turbine as shown in the diagram given below: The area of shaded region is 1000 Nm. What is the amount is turbine work done during the process?

The slope of log P-log V graph for a gas for isothermal change is m₁ and for adiabatic changes is m₂. If the gas is diatomic gas, then

Air is being forced by the bicycle pump into a tyre against a pressure of 4-5 bars. A slow downward movement of the piston can be approximated as

The change in specific entropy of a system undergoing a reversible process is  given by    This is valid for which one of the following?

Change in enthalpy in a closed system is equal to the heat transferred, if the reversible process takes place at

A saturated vapour is compressed to half its volume without changing its temperature. The result is that:

Which one of the following thermodynamic processes approximates the steaming of food in a pressure cooker?

A system at a given state undergoes change through the following expansion processes to reach the same final volume

1. Isothermal

2. Isobaric

3. Adiabatic ( γ = 1.4)

4. Polytropic(n =1.3)

The correct ascending order of the work output in these four processes is

Four processes of a thermodynamic cycle are shown above in Fig.I on the T-s plane in the sequence 1-2-3-4. The corresponding correct sequence of these processes in the p- V plane as shown above in Fig. II will be

A perfect gas at 27°C was heated until its volume was doubled using the following three different processes separately

1. Constant pressure process

2 Isothermal process

3. Isentropic process

Which one of the following is the correct sequence in the order of increasing value of the final temperature of the gas reached by using the above three different processes?

Assertion (A): For a perfect gas, hyperbolic expansion is an isothermal expansion.

Reason (R): For a perfect gas, PV/T = constant.

An ideal gas with initial volume, pressure and temperature of 0.1 m³, 1bar and 27°C respectively is compressed in a cylinder by a piston such that its final volume and pressure are 0.04 m3 and 5 bars respectively, then its final temperature will be:

An Ideal gas with initial volume, pressure and temperature of 0.1m³, 1 bar and 27°C respectively is compressed in a cylinder by piston such that its final volume and pressure 0.04 m3 and 5 bar respectively, then its final temperature will be:

​If a gas obeys van der Waals' equation at the critical point, then   is equal  to which one of the following

A higher value of Van der waal‟s constant for a gas indicates that the

Consider the following statements:

1. During a reversible non-flow process, for the same expansion ratio, work done by a gas diminishes as the value of n in pvⁿ = C increases.

2. Adiabatic mixing process is a reversible process.

Which of the statements given above is/are correct?

In a reversible isothermal expansion process, the fluid expands from 10 bar and 2 m³ to 2 bar and 10 m³. During the process the heat supplied is at the rate of 100 kW. What is the rate of work done during the process?