The changes which occur in a short period in known as __________ change.
Fast
Slow
Desirable
None of these
Growing of plant into a tree is a __________ change.
Chemical
Physical
Permanent change.
Burning of coal is ____________ change.
endothermic
exothermic
periodic
none of these
Periodic change may be used for measuring
Time intervals
Fixed intervals
Prolonged intervals
Regular intervals.
Melting of solid and freezing of liquid are __________ changes.
Undesirable.
Heart beat is a _________ change.
None periodic
Periodic
Reversible
Irreversible change.
Curdling of milk is an __________ reaction.
both A&B
The changes which are brought and controlled by man is called
Natural changes
Nan made changes
Chemical changes
Physical changes
___________is the chemical reaction in which heat and light are formed in the form of flame.
Burning
Melting
Rusting of iron
Sublimation.
Dissolution of solid in liquid (ie sugar in water) is a __________ change.
Undesirable
