Hi Dr. Sharma, I was doing Quiz 6.1 and I ran into two problems that I have some difficulty in solving. I reviewed the notes but I am still slightly confused. Can you please explain these two problems:

 

Potassium metal is the most reactive metal with minimum molar mass in the list of compounds and elements in the option. So moles of K are more and hence with potassium it is the largest amount of energy released  with largest amount of hydrogen gas .So entropy is more because Hydrogen gas formed is more and enthalpy is also more as more moles of K gives more energy during the reaction.
Δ G = ΔH-TΔS
More negative ΔH and more positive ΔS results in very negative ΔG.More negative ΔG results in high free energy released.ΔG we will do in unit 9.


In the second question-container is non rigid so means volume is flexible.
Flexible container properties: A non-rigid container does not have a fixed volume. Its volume changes depending on the pressure difference between the gas inside and the external surroundings.

Pressure and force relationship: As the gas inside the container exerts pressure, it applies a force outward. This force can cause the walls of the container to expand.

Expansion with increasing pressure: If the internal pressure of the gas becomes greater than the external pressure (e.g., atmospheric pressure), the container will expand, increasing the volume of the gas.
So the system is doing work on the surroundings so all energy is converted into work.