Question

Another real-world example of a change is rust. Rust is iron(III) oxide (Fe2O3), which results when iron is exposed to oxygen and water.

What are some indicators of rusting? Check all that apply.

production of light

color change

formation of a solid

formation of a gas

Answer 1

- color change — Yes (iron develops a reddish-brown color)
- formation of a solid — Yes (rust, a new solid, forms on the metal)

Not these:
- production of light — No
- formation of a gas — No