entropy

  1. S

    understanding

    i forgot the concepts understanding word by word without practical imaginative thinking. how to understand chemistry like a story. can anyone can tell me
  2. D

    entropy change adiabatic expansion

    Hello all, this may be a silly question , but for some reason I can't seem to find an explanation anywhere... When an adiabatic process is reversible, why is the entropy=0 (which is not true for an irreversible) using equation, I understand why this is true (since Q=0) but conceptually I'm...
  3. J

    Entropy

    Q] Calculate the change in molar entropy when a monoatomic gas is compressed from 2.0 dm^3 to 500 cm^3 and simultaneously heated from 300K to 400K. Take Cv,m = 3R/2. I tried splitting it into a) constant volume process and b0 constant temperature process and adding the two entropies but that...
  4. K

    entropy question HELP

    Hi guys! This is my first time posting here. I'm currently studying chemistry and have questions about entropy. First, I want to check a few things that I know of entropy. Please correct me if I know it wrong. -it increases when solid->liquid->gas -it increases when breaking the bond -it...
  5. K

    simple entropy Q HELP!

    Hi guys! This is my first time posting here. I'm currently studying chemistry and have questions about entropy. First, I want to check a few things that I know of entropy. Please correct me if I know it wrong. -it increases when solid->liquid->gas -it increases when breaking the bond -it...
  6. B

    Help with entropy prob

    The reaction: NH3 + HCl ---> NH4Cl happens at the same temperature in gas phase and in a solution. If we assume the mobility of the molecules in both phases is the same, does Δs in the gas phase differ from the Δs in the liquid phase? Explain.
  7. P

    Adiabatic entropy change

    For an adiabatic process dQ=0, there is no heat exchange with the surroundings, therefore dS(surroundings)=0. For expansion of an ideal gas, so the dS(total) must either be = 0 (in the case of a reversible change) or it must increase (second law). In the case of the dS(total) increasing the...
  8. I

    Does this reaction have a critical temperature?

    2 CCl4 (g) + O2 (g) --> 2COCl2(g) + 2Cl2(g) Predict the sign of ΔS, as the reaction proceeds to the right: the products have a higher ΔS because there are more mols of gaseous products than reactants. ΔG and ΔH are also positive at room temp. (it's not spontaneous). So does this reaction have...
  9. C

    Thermodynamics

    Which term, the standard molar entropy( delta S knot) or the standard free energy (delta G know) is the most important in determining the relative strength in the series of acids? I have been stuck on this question for a while, both terms tell us how spontaneous a reaction is, which one is more...
  10. C

    Thermochemistry:Gibbs' Free Energy and Entropy

    1. The problem statement, all variables and given/known data a) 3 moles of carbon dioxide gas expands reversibly in a piston-container from 20 L to 40 L in an isothermal process at 400 K. Calculate work, heat, change in internal energy and change in enthalpy, considering van der Waals...
  11. J

    Entropy

    apparently ΔS° (standard entropy change) is the change in entropy between the state of interest and when the material is at 0K OR 0C (not sure which one, could someone please clarify) and ΔS (entropy change) is the change in entropy between two states and are they both calculated in the same...
  12. H

    entropy change

    when water freeze, 6 kj/mol of heat enthalpy is evolve. what is the the entropy change when 54g of water freeze at 0 degree celsius?
  13. T

    Question about entropy

    I've learned that higher entropy means that a system can take on more states. What exactly does the word "state" mean in this context? Let's say you have some gas in a container, and you increase the volume. Now the same gas molecules occupy a larger area. Does the system now have higher...