Question

which of the following is not a physical change? * 2 points

• grating cheese
• melting cheese
• processing/creating cheese
• mixing two cheeses in a bowl

all of the following changes to a metal are physical changes except * 2 points

• bending
• melting
• rusting
• polishing

a chemical change occurs when a piece of wood * 2 points

• is split
• decays
• is painted
• is cut

Explanation:

1. Physical changes do not change the chemical composition of a substance. Grating, melting, and mixing cheese are physical changes as the cheese's chemical makeup remains the same. Processing/creating cheese involves chemical reactions like curdling milk, so it is not a physical change.
2. Bending, melting, and polishing metal are physical changes as they only alter the physical form. Rusting is a chemical change as iron reacts with oxygen to form iron oxide.
3. Splitting, painting, and cutting wood are physical changes. Decaying wood is a chemical change as microorganisms break down the wood's organic matter through chemical reactions.

Answer:

1. C. processing/creating cheese
2. C. rusting
3. B. decays