Different Types Of Thermodynamic Process At A Glance


Change or name of the process Isobaric Isochromic Isothermal Adiabatic


Definition P = Constant V = Constant T = Constant a) Q = Constant

b) Entropy

S = Constant

2. dQ 1. For solids

dQ = mcpdT

For gases ncvDt

2. For change in state

dQ = mL

1. For solids

dQ = mcvdT

For gases ncvdT

dQ = dW



dU 1. dQ-pdV

2. dQ-nRdT

dQ Zero -dW
4. dW 1. PdV

2. nRdT

Zero 2.303n Rt log v₂/v₁

2.303n p₁v₁ log v₂/v₁

2.303n p₁v₁ log p₂/p₁

\[\frac{R\left( {{T}_{2}}-{{T}_{1}} \right)}{1-\gamma }\]

\[\frac{\left( {{P}_{2}}{{V}_{2}}-{{P}_{1}}{{V}_{1}} \right)}{1-\gamma }\]


Equation of state V/T = Constant P/T = Constant PV = Constant

P₁V₁ = P₂V₂



P1-γ Tγ=constant


Slope of p – v curve Zero -p/v

– γP/v

7. Law Charle’s law Gay-lussac’s law Boyle’s law

Poisson’s law


Form of First laws dQ = dU + dW = ncpdT + PdV dQ = dU = ncvdT dQ = dW = dV – dU = dW
9. Bulk modulus Zero Infinity -p


10. Result of maximum work Maximum Zero Less from isobaric process but greater form adiabatic process

Minimum but not zero

Example: A cylinder with a movable piston contains 3 moles of hydrogen at standard temperature and pressure. The walls of the cylinder are made of a heat insulator, and the piston is insulated by having a pile of sand on it. By what factor does the pressure of the gas increase if the gas is compressed to half its original volume?

Ans: As no heat is allowed to be exchanged, the process is adiabatic.

As V₂ = V₁/2.