Question

Consider the following properties:
I) Objects made of silver become tarnished.
II) The red color of rubies is due to the
presence of chromium ions.
III) The boiling point of ethanol is 78◦
Which is/are chemical?

Answer 1

tarnishing/rusting is a chemical rection with the oxygen in the atmosphere

chromium's electrons allowed energy sates are responsible for the colour its molecules appear