Question

Iron garden tools were left outside over the winter. When found, They appeared dirty with spots of reddish-brown, flaky substance. Was this a physical or chemical change? How do you know?​

Answer 1

Chemical change

Step-by-step explanation:

The reddish-brown substance is rust. Rust is a chemical change because rust is a different kind of matter than the iron, oxygen, and water present before the rust formed. The explosion of nitroglycerin is a chemical change because the gases produced are very different kinds of matter from the original substance.