Recent content by il postino

  1. il postino

    Chemistry Calculate the solubility (common ion) buffered

    Data: ## pK_{ps} , pKa_{1} , pKa_{2} ## Could you guide me to start solving? Thank you!
  2. il postino

    Chemistry Calculate the activity of the chloride ion in a solution

    aCl−=mCl−∗γCl− Muchas gracias Borek! (In Argentina jaja) Thanks!
  3. il postino

    Chemistry Calculate the activity of the chloride ion in a solution

    ##m_{Cl}*\gamma _{Cl}## ##log(\gamma _{Cl})=-A.|Z|.\sqrt{I}## If I calculate ##\gamma _{Cl}## can I calculate the activity without problems?
  4. il postino

    Chemistry Calculate the activity of the chloride ion in a solution

    0.0014m + 0.0012m = 0,0026m How do I continue? Thanks Borek
  5. il postino

    Chemistry Calculate the activity of the chloride ion in a solution

    Hi everyone! I have to calculate the activity of ##Cl^{-}## I have a solution formed by ## Na_{2}SO_{4}## 0.0016 m + ##NaCl## 0.0014m + ##FeCl_{3}## 0.0012m I calculated the ionic strength ##I## ##I=0.0134## The activity of the chloride ion is ##a_{Cl^{-}}=m_{Cl}*\gamma _{Cl}## But I don't...
  6. il postino

    Chemistry How Many Extractions Are Needed to Reduce Stearic Acid to 0.08%?

  7. il postino

    Chemistry How Many Extractions Are Needed to Reduce Stearic Acid to 0.08%?

    Hi all! The distribution constant of stearic acid between n-heptane and acetic acid is 4.95 at 25 ° C. Determine the number of extractions from a solution of stearic acid in acid acetic acid, with successive portions of n-heptane of equal volume to the solution, necessary to reduce the residual...
  8. il postino

    Chemistry Relationship between ppm and mole fraction

    Hi all! I have a question ... I have to calculate the partial pressure of O2 Ccan I calculate the mole fraction from the data of 1 ppm of O2? The total pressure is 760 torr Thank you!
  9. il postino

    Chemistry Calculate DeltaH between 700K and 800K

    Excuse me Mjc, I can't understand yet.
  10. il postino

    Chemistry Calculate DeltaH between 700K and 800K

    Hi all Knowing that ##kp## is: ##k_p=\frac{pO_2.(pNO)^2}{(pNO_2)^2}## And knowing these relationships between the partial pressures, I obtained: At 700 K: ##pNO = 0.872.pNO2## ##k_p=pO_2.(0.872)^2## At 800 K: ##pNO = 2.5.pNO2## ##k_p=pO_2.(2.5)^2## Furthermore it is known that ##pNO + pNO +...
  11. il postino

    Chemistry Calculate the boiling temperature of methanol from thermodynamic data

    Thank you very much Chester! You made me not only want to find the solution, but also LEARN more! We will surely meet here! Thank you very much! Greetings from Argentina! :smile::smile:
  12. il postino

    Chemistry Calculate the boiling temperature of methanol from thermodynamic data

    Hi Chester! you mean the 2 points ##(P; T)##: ##(2.144 ; 359.1)## and ##(78 ; 513)## For these points, the linear equation is: ##y = -0,0002x + 0,003## For ##ln (60)##, ##1/T## it gives me a very high and negative number. What am I doing wrong? Also, I know that the slope of that line...
  13. il postino

    Chemistry Calculate the boiling temperature of methanol from thermodynamic data

    Okey :) I will and inform you! Thank you!
  14. il postino

    Chemistry Calculate the boiling temperature of methanol from thermodynamic data

    Then I am very happy! :bow: Now I understand better with your explanation. How can I continue?
  15. il postino

    Chemistry Calculate the boiling temperature of methanol from thermodynamic data

    Hi Chester! I was investigating what you taught me. With that formula I can get the reduced pressure: ##P_{r}=0.0277## and knowing that ##P=P_{r} * P_c## ##P=2.16 atm## On the other hand, I am considering that ##T_{r}=0.7## Thus ##T=0.7*513K=359.1 K## It is right? If this is correct, you...