because it can no be reversible
once it has been burnt it cannot be turned back into bread or slightly toasted toast, that is its permanent form
:D
Burning is an oxydation reaction so a chemical change.
an example of a chemical change is burning. there are, of course, many others.
Melting: change of phase, a physical phenomenon without change of the composition. Burning: a reaction of oxydation, a change of composition - a chemical change.
Burning is a chemical change.
Lighting A Match
For example burning of coal is a chemical change.
Burning of a matchstick.
burning paper
Combustion (burning) is a chemical change.
burning of wood is a chemical change as it produces heat and cutting it into small pieces is a physical change as there is a change in shape and size.
Burning of paper is actually an example of a chemical change, not a physical change. During burning, the chemical composition of the paper changes as it reacts with oxygen to produce new substances like ash, water vapor, and carbon dioxide.
A tree burning down and becoming ash