Question

How is chemical change defined?

Answer 1

Chemical change is characterized by..........

Explanation:

Chemical change is characterized by the formation of new substances and the making and breaking of strong chemical bonds. And I wish I had a fiver for every time I have said that here.....

Mix iron and sulfur flowers in a mortar, and NO chemical change takes place...... How do you know? Well you could take a magnet to the powder and separate the iron filings.

Heat the mixture, and the iron is oxidized......i.e. according the reaction.....

`Fe(s) + S(s) stackrel(Delta)rarr FeS(s)`

Iron sulfide is a powdery black solid, insoluble in just about everything. The oxidized iron of the sulfide is no longer attracted to the magnet.....