Isothermal Definition and 227 Threads

In thermodynamics, an isothermal process is a type of thermodynamic process in which the temperature of the system remains constant: ΔT = 0. This typically occurs when a system is in contact with an outside thermal reservoir, and the change in the system will occur slowly enough to allow the system to continue to adjust to the temperature of the reservoir through heat exchange (see quasi-equilibrium). In contrast, an adiabatic process is where a system exchanges no heat with its surroundings (Q = 0).
Simply, we can say that in isothermal process




T
=

constant



{\displaystyle T={\text{constant}}}





Δ
T
=
0


{\displaystyle \Delta T=0}





d
T
=
0


{\displaystyle dT=0}

For ideal gases only, internal energy



Δ
U
=
0


{\displaystyle \Delta U=0}
while in adiabatic processes:




Q
=
0.


{\displaystyle Q=0.}

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  1. AEGIS

    Adiabatic or Isothermal? Compressed air energy storage

    Hi, I'm doing a high school physics project and am trying to figure out if a certain setup that I'm using is adiabatic or isothermal, in order to determine what equation I can use to calculate the work that my setup does-- the threads I've come across so far only explain the difference, but not...
  2. T

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  3. H

    Does this wave propagation problem make physical sense?

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  4. fricke

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  5. J

    Isothermal Compressibility: Derive an equation

    > The isothermal compressibility $\kappa_t$ of a substance is defined as $$ \kappa_t = -\frac{1}{V} \left ( \frac{\partial V}{\partial P} \right )_T $$ Obtain an expression for the isothermal compressibility of an ideal gas. (PV = RT) in terms of p. I believe that the ideal gas law equation...
  6. leafjerky

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  7. C

    Work of isothermal compression at constant pressure

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  8. A

    I want to know the differences about isothermal process.

    I'm sorry for bad english. I wonder what is the differences between reversible-isothermal-expansion and irreversible-isothermal-expansion. Is their entropy same?
  9. S

    Adiabatic Free Expansion and Reversible Isothermal Path

    Homework Statement Consider an ideal monatomic gas that undergoes an adiabatic free expansion starting from equilibrium state A with volume 500 cm3, pressure 40 kPa and temperature 300K to state B, which has a final equilibrium volume of 1000 cm3. Construct an reversible isothermal path that...
  10. barryj

    Work in isothermal PV process. Which method is correct?

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  11. AdityaDev

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  12. S

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  13. MexChemE

    Energy balance -- Physical interpretation of Q

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  14. C

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  15. S

    Work done isothermal, adiabatic ideal gas

    Problem statement, work done, and relevant equations: One mole of ideal gas is initially at 1 atm and has a volume of 5L. a) Calculate the work done on the gas during an isothermal, reversible compression to a volume of 2L. ##W_isothermal = - \int_{v_i}^{v_f} p dv = - \int_{v_I}^{v_f}...
  16. R

    Thermodynamics : Isothermal process

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  17. AdityaDev

    Why is P_ext different for reversible and irreversible isothermal expansion?

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  18. A

    Why are isothermal process values higher than adiabatic ones?

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  19. Z

    How to Calculate Isothermal Compressibility for Question 6b?

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  20. C

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  21. M

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  22. M

    Isothermal Expansion of a Diatomic Gas

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  23. MexChemE

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    Homework Statement Find ΔH for the isothermal expansion of one mole of CO2 from a pressure of 1 atm to zero at 300 K. The critical point of CO2 is TC = 31 °C and PC = 73 atm. Use the equation for ΔH you previously derived from the Berthelot equation of state. (Answer provided by textbook: ΔH =...
  24. L

    How Much Work Is Done in an Isothermal Expansion?

    I made a thread on this asking the general question in the other forum, but I don't know how to delete that thread. Homework Statement An isothermal expansion from Vi = 10.0 L, Pi = 2.46 atm against a constant external pressure until the Pf = 0.246 atm. How much work is done by the gas in...
  25. C

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  26. C

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  27. F

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  28. A

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  29. O

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  30. PhizKid

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  31. J

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  32. M

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  33. R

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  34. M

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  35. Entanglement

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  36. Feodalherren

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  37. J

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  38. P

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  39. T

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  40. M

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  41. M

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  42. P

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  43. A

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  44. F

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  45. F

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  46. J

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  47. A

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  48. S

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  49. W

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  50. T

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