1. Mechanically removing: physical process
2. Chemically removing: chemical process
Physical change
Removing tarnish from a penny with salt and vinegar is a chemical change. The reaction between the salt, vinegar, and tarnish on the penny results in the formation of new substances that remove the tarnish.
Chemical Change.--its tarnish!
Chemical Change.--its tarnish!
Chemical Change.--its tarnish!
It is a chemical change. Oxygen from the air combined chemically with the silver to form silver oxide- that is the tarnish.
It is a chemical change.
This is a chemical change.
It's a chemical change because a new substance comes out of tarnishing.
Evaporation is a physical change.
The tarnishing of silver is due to a reaction with hydrogen sulfide. Because the end result of the tarnish is silver sulfide, it is a chemical change.
It's a chemical change. A thin layer of silver on the surface reacts with oxygen in the air - to form silver oxide.