The given compound is 
Each formula unit of
has 2 mol Potassium (K) atoms, 2 mol Chromium (Cr) atoms and 7 mol Oxygen (O) atoms.
Atomic weight of potassium is 39.0983 amu
Atomic weight of Chromium is 51.9961 amu
Atomic weight of Oxygen is 15.9994 amu.
Therefore the formula weight of 

= 294.1846 amu
Potential Energy is the stored energy in an object or system because of its position or configuration. Kinetic energy of an object is relative to other moving and stationary objects in its immediate environment.
The answer for this is 26.6°c
Answer:
2.677 J/g°C
Explanation:
Quantity of heat required to raise the temperature of the metal,
Q = mc∆T
where m is the mass of the metal, c is the metal's specific heat capacity, and ∆T is the change in temperature that accompanies the heat transfer process
20.0J = 50.0g × c × 150°C
c = 20.0J/(50.0g × 150°C)
c = 2.677 J/g°C
Isn't that a substitution reaction? Sorry if i am wrong haven't taken these in a while