Textbook Problem

Classify each of the following as a physical or chemical change or property.

1. Oven cleaners contain sodium hydroxide, which converts the grease/oil spatters inside the oven to water-soluble materials, which can be washed away.

A rubber band stretches when you pull on it.

A cast-iron frying pan will rust if it is not dried after washing.

Concentrated hydrochloric acid has a choking, pungent odor.

Concentrated hydrochloric acid will burn a hole in cotton jeans because the acid breaks down the cellulose fibers in cotton.

Copper compounds often form beautiful blue crystals when a solution of a given copper compound is evaporated slowly.

Copper metal combines with substances in the air 10 form a green “patina” that protects the copper from further reaction.

Bread turns brown when you heat it in a toaster.

When you use the perfume your boyfriend gave you for your birthday, the liquid of the perfume evaporates quickly from your skin.

If you leave your steak on the gas grill tot) long, the steak will turn black and char.

Hydrogen peroxide fizzes when it is applied to a cut or scrape.