I know that heat is energy in transit. In other words, there is heat transfer because particles (of the hotter object) impart their kinetic energy to other particles (of the colder object) through collisions.
1) So, what is the difference between heat and kinetic energy ?
One particular source says that there is no difference between the two and that "heat is the kinetic energy stored microscopically as random motion of many particles". But another source says that heat cannot be stored. I am completely confused.
2) This is another definition I found:
"heat Q is defined for a given process as the internal energy interchanged which is neither work nor due to flow of matter
Notice that internal energy is a state function and ΔU denotes the difference between the initial and final energies, but heat is not a state" function and this is why we write Q instead of an incorrect ΔQ"
This one seems to have more depth but I just cannot understand what the author means when he says "which is neither work nor due to flow of matter".