Question

While studying chemical and physical changes, students added salt to a glass of water. They stirred the salt until it dissolved and could no longer be seen. "That's a chemical change," Sarah stated. Do you agree? Explain. A) Yes, it is a chemical change because something new is formed. B) No, it is a physical change. It is salt and water and you can get the salt back by boiling off the water. C) Yes, it is a chemical change because there was a change in the appearance of one of the components, the salt. D) No, it is a physical change. A chemical change cannot occur when you mix two compounds together like salt, NaCl, and water, H2O, without adding heat.

Answer 1

B. It's debatable if it's a physical or chemical change, because actual chemists don't have a hard distinction between the two.

Answer 2

B. It's debatable if it's a physical or chemical change, because actual chemists don't have a hard distinction between the two.