How does the content on elements and compounds relate to something you are interested in? Describe that connection to the rest of the class and be sure to include a relevant photo or Weblink.

We live in an atmosphere of 21% oxygen. A match burns in less than a minute, a fireplace consumes a small pine log in about 20 minutes, and we exhale about 15 times a minute. Life on Earth would be very different if the oxygen concentration were twice as high. List at least four ways the Earth or our lives might be different with such an increased amount of oxygen.