Growing of plant into a tree is a __________ change.

Burning of coal is ____________ change.

Periodic change take place repeatedly after a certain _________ of time.

The changes which occur in a short period in known as __________ change.

A change which is useful to us is a _________ change.

The change which take longer time to occur are called ___________ change.

Curdling of milk is an __________ reaction.

___________ is the process where a solid turns directly into gas without entering to the liquid liquid slate.

___________ is an exothermic reaction.

  Sublimation  is a ___________ change.