S1, Ep 10: Differences between metals and nonmetals

Caroline Christian, Ph.D.

Another common problem I see in chemistry classes is knowing which elements form cations and which form anions, or knowing which elements are metals and which are nonmetals. Metals will form cations, because they want to lose electrons and become positively charged. (Remember my first blog post about electrons? If not, click here!) Nonmetals form anions because they want to gain electrons and become negatively charged. From our periodic table in this figure:

The elements on the left side of the periodic table, or the elements in blue are metals. The elements on the right are nonmetals or the elements in tan. The elements in green are metalloids or semimetals, they have properties that are in between metals and nonmetals. Here is a good website that lists the physical and chemical differences between metals and nonmetals. Metals are good conductors of heat and electricity, they have high melting points and densities, and they lose electrons easily. Nonmetals on the other hand, are poor conductors of heat and electricity, and they gain electrons easily. The interesting thing I think about metals and nonmetals is that even though there are so many more metals than nonmetals, nonmetals are mostly what are found in our bodies. We are carbon based, with lots of organic molecules (mostly carbon and hydrogen), we need oxygen to breathe, and most of our atmosphere is made up of nitrogen. I really love biochemistry, but that is a blog post for another day! Thanks for reading. Next week we will explore nuclear chemistry.

03/16/2018