You accidentally dropped your favorite toy and broke it. This is a change you did not want. Can this change be reversed?

Changes in the shape/nature of an object can be of two types. They are reversible changes and irreversible changes.

a) The changes in which the object/matter can be brought back to its original state are known as reversible changes.

    e.g., melting of wax, stretching of a rubber band, etc.

b) The changes in which the object/matter cannot be brought back to its original state are called irreversible changes.

    e.g., burning of wood, cooking of food, etc.

No, the toy is already broken and cannot be restored to its exact initial condition; as a result, this change cannot be reversed. It is therefore an irreversible change.