A. examining the structure of plant cells
Incorrect. A biologist is required.
B. building a fence
Incorrect. A carpenter is required.
C. building a wood storage shed
Incorrect. A carpenter is required.
D. testing a rock sample for gold content
Incorrect. A chemist is required.
A. creating salt by reacting sodium metal and chlorine gas
Incorrect. This is a chemical change as a new product is formed.
B. allowing a nail rust
Incorrect. This is a chemical change as it is the oxidation of iron to form iron oxide, rust.
C. separating a salt solution by evaporating the water
Correct. This is a physical change as salt gets separated from water and no new product is formed.
D. building a model rocket propelled by mixing baking soda and vinegar
Incorrect. This is a chemical change.
