These are always inherently instructor-dependent questions. If the courses are taught for the ACS Inorganic and ACS Physical Chemistry (thermodynamics and kinetics exams) then they will be difficult. Generally, if taught correctly, Pchem will challenge your ability to utilize mathematical skills that are (depending on yourself as a student) already conceptually tricky, for the solution of problems in chemistry.
Thermodynamics is particularly difficult, in my opinion, because it's very dry. From my QM professor, his quote puts it quite aptly, "Thermodynamics is sort of like a physical chemist's vegetables - not very tasty but necessary for growth into quantum mechanics and more interesting, dessert-like topics." Thermo was difficult for me because it largely stemmed from the 5 state equations, showing that you can get any information you need on the thermodynamic parameters of a system knowing a few basic properties and how the equations relate to one another; in short, it's a lot of the same thing re-wrapped with several proofs to make it still memorization-heavy. Pchem kinetics were far more interesting, in my opinion. Quantum is the best of all physical chemistry courses in terms of interest-factor.
As far as inorganic goes, there is much more rote memorization in terms of point groups, packing groups, symmetry, etc. It's a bit like gen chem III where the individual problems and concepts are not hard, but there is a lot to remember and, unless you like geometry and what not, it's a bit dry.
Like I said, if these courses are taught for the ACS exams, one for inorganic, and two individual ones for Pchem being kinetics and thermodynamics, they will probably be challenging. So, the first step at gauging that is to find out if you'll be taking the ACS exams.