Question

Which is the only physical change?
A. the souring of milk
B. the burning of oil
C. the melting of ice
D. the rusting of iron

Answer 1

C) the melting of ice
all the other choices are processes that produce additional chemicals not present in the beginning of the reactions.

in the melting of ice, no new substances or chemicals are formed. water is present in the beginning and still present in the end. it's just in the liquid form instead of the solid form.