Question

Some silverware is made with the element silver (Ag). Over time, this silverware will turn black (tarnish) if it is not cleaned with a special solution. Why is this a chemical change?

Answer 1

The tarnish is actually the result of a chemical reaction between the silver and sulfur-containing substances in the air. The silver is actually combining with sulfur and forming silver sulfide. Silver sulfide is black. When a thin coating of silver sulfide forms on the surface of silver, it darkens the silver. That’s what we call ‘tarnish.’