Question

What do these two changes have in common? Select all that apply.

rust forming on a metal gate
snails growing shells
(1 point)
Responses

Both are changes in state
Both are changes in state

Both conserve mass
Both conserve mass

Both are chemical changes
Both are chemical changes

Both are only physical changes

Answer 1

- Both conserve mass
- Both are chemical changes

Explanation: Rusting is a chemical reaction (iron + oxygen → iron oxide). Snail shell formation is a biological/chemical process where the snail deposits minerals (e.g., calcium carbonate). In both cases chemical reactions occur and mass is conserved overall. They are not changes of state nor only physical changes.