Chemical Engineering Thermodynamics - Study Mode

[#331] In the equation, PV n = constant, if the value of n is in between 1 and y $$left( {{ ext{i}}{ ext{.e}}{ ext{., }}frac{{{{ ext{C}}_{ ext{P}}}}}{{{{ ext{C}}_{ ext{V}}}}}}
ight),$$ xa0 then it represents a reversible __________ process.
Correct Answer

(B) Polytropic

Explanation

Solution: $$P{V^n} = { ext{constant}},$$ xa0 xa0if $$n$$ lies between the $$1$$ and $$yleft( {frac{{{c_p}}}{{{c_v}}}}
ight)$$ xa0then the process is known as polytrophic process when $$n = 1$$ xa0it is called isothermal process and when $$n = y$$ xa0it is called as adiabatic process.

[#332] In the equation, PV n = constant, if the value of $${ ext{n}} = pm infty ,$$ xa0 then it represents a reversible __________ process.
Correct Answer

(B) Isometric

Explanation

Solution: Since when $$n = pm infty $$ xa0 the equation $$P{V^n} = { ext{constant}}$$ xa0 xa0 is leading to volume $$=$$ constant the process is called as isochoric process on multiplying the power with $$frac{1}{infty }$$ we get the equation $$v = { ext{constant}}.$$

[#333] Which of the following is not correct for a reversible adiabatic process?
Correct Answer

(D) None of these

Explanation

Solution: An adiabatic process is represented by $$p{v^gamma } = { ext{constant}}$$ xa0 xa0now by replacing the $$p$$ with $$frac{{nRT}}{v}$$ xa0we get $$T{V^{gamma - 1}} = { ext{constant}}$$ xa0 xa0and by replacing the $$V$$ with $$frac{{nRT}}{P}$$ xa0we get the equation $${P^{1 - gamma }}{T^gamma } = { ext{constant}}.$$

[#334] Requisites of a reversible process is that the
Correct Answer

(B) Friction in the system should be absent

Explanation

Solution: A reversible process is such a process where the system and surroundings must be brought to the initial positions when the system is brought to initial position for that to achieve the system should not contain friction.

[#335] Third law of thermodynamics is concerned with the
Correct Answer

(A) Value of absolute entropy

Explanation

Solution: Third law of thermodynamics tells about entropy it says that entropy becomes constant at absolute zero temperature. There are some deviations observed from this law for some substances.