Question

question 3. classify each of the following as a physical or chemical change. a) ice melting. b) paper burning. c) metal rusting. d) liquid evaporating. e) digesting food. f) tearing a sheet of paper. g) burning a log. physical change chemical change

Explanation:

• Physical change: No new substances are formed, only a change in state or form. Chemical change: New substances are formed with different chemical properties.
• a) Ice melting is a phase - change from solid to liquid without a change in chemical composition, so it's a physical change.
• b) Paper burning produces new substances like carbon dioxide and ash, so it's a chemical change.
• c) Metal rusting is a chemical reaction between metal, oxygen, and water to form metal oxide, so it's a chemical change.
• d) Liquid evaporating is a phase - change from liquid to gas without a change in chemical composition, so it's a physical change.
• e) Digesting food involves chemical reactions to break down food into nutrients, so it's a chemical change.
• f) Tearing a sheet of paper only changes its physical form, not its chemical composition, so it's a physical change.
• g) Burning a log produces new substances like carbon dioxide, water vapor, and ash, so it's a chemical change.

Answer:

a) Physical Change
b) Chemical Change
c) Chemical Change
d) Physical Change
e) Chemical Change
f) Physical Change
g) Chemical Change