Online Calculators since 2009
The Entropy Calculator will calculate the:
Note: Write the ΔQ value as negative when the system releases heat to its surroundings.
The change in the entropy of a thermodynamic system in terms of heat exchanged and temperature of system is:

The change in the entropy of a thermodynamic system in terms of volume, temperature and molar specific heat at constant volume J/K 
The change in the entropy of a thermodynamic system in terms of pressure, temperature and molar specific heat at constant pressure J/K 
Change in entropy of system in terms of heat and temperature calculations 

Hot object calculation∆S_{1} = ∆Q/T_{1}∆S_{1} = /T_{1} ∆S_{1} = Cold object calculation∆S_{2} = ∆Q/T_{2}∆S_{2} = / ∆S_{2} = Universe calculation∆S_{universe} = ∆S_{1} + ∆S_{2} 
Change in entropy in terms of V, T and C_{V} calculation 
∆S = C_{V} × lnT_{2}/T_{1} + R × lnV_{2}/V_{1} ∆S = × ln/ + × ln/ ∆S = × ln() + × ln() ∆S = × + × ∆S = 
Change in entropy in terms of P, T and C_{P} calculation 
∆S = C_{P} × lnT_{2}/T_{1}  R × lnP_{2}/P_{1} ∆S = × ln/  × ln/ ∆S = × ln()  × ln() ∆S = ×  × ∆S = 
Entropy Calculator Input Values 
Initial pressure of gas (P_{1}) Pa 
Initial volume of gas (V_{1}) m^{3} 
Initial temperature of gas (T_{1}) K 
Final pressure of gas (P_{2}) Pa 
Final volume of gas (V_{2}) m^{3} 
Final temperature of gas (T_{2}) K 
Heat exchanged during the process (ΔQ) J 
Ideal gas constant (R) J/mol∙K 
Molar specific heat at constant volume (C_{V}) J/mol∙K 
Molar specific heat at constant pressure (C_{P}) J/mol∙K 
Please note that the formula for each calculation along with detailed calculations are available below. As you enter the specific factors of each entropy calculation, the Entropy Calculator will automatically calculate the results and update the Physics formula elements with each element of the entropy calculation. You can then email or print this entropy calculation as required for later use.
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