If you cut the cube and keep all the pieces you are causing only physical change
There are 4 things that are evidence of a chemical change.
1)Change in color
2)Change in shape (gas being let out)
3)Change in temperature
4)Change in smell
Burning wood is a chemical change because it has a change in color, and shape.
H20. 2 of hydrogen and oxygen
The iron nail displaces the Cu from the copper sulfate solution. This results in the color of CuSO4's disappearance. Copper is less reactive than iron.
