I don't think so. No way that I know anyway. It it could be done then the need for more coal to be mined would have stopped hundreds of years ago. Once coal is burned, it forms water and carbon dioxide (essentially) with some sulfur oxides.
How do you put that back together again. It's a little like humpty dumpty.
Answer:
Explanation:
It depends on how this is done. If you raise the pressure, the nitrogen will disappear (liquify) and all that will be left will be the 21 % oxygen and the 1% argon.
The process is very complicated because the boiling point of nitrogen keeps on changing. The boiling point is unstable.
I would think it is a heterogeneous mixture since it can't be an element since there are more than one type of atom, it can't be a compound since the leaves are not bonded together, and it can not be a homogeneous mixture since the leaves don't all blended together (the pile is not uniform) and you can distinguish all the different parts of the mixture. It can be considered a heterogeneous mixture since the leaves are mixed together (along with other things like dirt) in a non-uniform way so that you can point out the parts of the mixture and it does not look like one thing.
I hope this helps. Let me know in the comments if anything is unclear.