Answer:
you can do a celser lava lamp its really easy, i can give you a link if you need?
Explanation:
Sawing a board in half is a physical change not a chemical change the board doesnt change wood or whatever material it is is still would still be wood
If it were burned it would be a chemical change but its properties stay the same atomically so thats why its not a chemical change.
Mole is mass (g) / Molar mass (mole/gram)
So to find mass in gram multiply the no.mole by Molar mass