Subject :NSO Class : Class 7
Kriti performed the following two experiments.
I. She held a hack-saw blade with a pair of tongs
and then kept the tip of the free end on the
flame. She observed that the blade became
red hot.
II. She dropped a shaving blade into the blue coloured
copper sulphate solution. The colour of the solution
changed to green.
Identify the types of changes occurring in both the
experiments.
A I - Physical change, II - Chemical change
B I - Chemical change, II - Physical change
C Both I and II - Physical changes
D Both I and II - Chemical changes