Answer the following in brief:
 
Define irreversible change
Answer variants:
burning
permanent
burnt substance
cooking
original object
new substance
original form
state
colour
An irreversible change is a change in which a substance or object cannot be changed back to its
or
. In this type of change, a
may be formed, and the change is usually
. Irreversible changes often occur during
,
, rusting, or breaking. For example, cooked food cannot be changed back into raw food again.