Answer:
a). ice melting is a physical change
b). paper burning is a chemical change
c). metal rusting is a chemical change
d). gas pressure increasing is a physical change
e). liquid evaporating is a physical change
f). food digesting is a chemical change
Explanation:
For all the above, In a physical change, the appearance or form of the matter changes but the kind of matter in the substance does not. However, in a chemical change, the kind of matter changes, and at least one new substance with new properties is formed.
a). ice melting - only form is changed
b). paper burning - By burning, ash is produced, which is different from paper
c). metal rusting - By rusting, the metal is oxidized and hence chemically changed
d). gas pressure increasing - only form is changed
e). liquid evaporating - only form is changed
f). food digesting - food is broken down into simpler molecules