The change in the standard free enthalpy is 341 kj at 25 oc

Question

Question 1:

For the reaction

A(aq) ---> B(aq)

the change in the standard free enthalpy is 3.41 kJ at 25 ^oC and 5.46 kJ at 45 ^oC. Calculate the value of this reaction's equilibrium constant at 75 ^oC. 

Question 2:

A container encloses 34.7 g of CO₂(g). The partial pressure of CO₂ is 2.77 atm and the volume of the container is 34.7 L. What is the average, or root mean square, speed (in m/s) of the CO₂ molecules in this container?

Question 3:

We have 500.0 mL of a buffer solution that is 0.629 M in NH₃ and 0.380 M in NH₄Cl. We add 500.0 mL of a solution 0.203 M in HCl. The final volume is 1.0000 L. The K_b value for NH₃ is 1.8 x 10^-5. What is the pH of the final solution?