National Chemistry Week - Elements in the Human Body
Sunday October 18, 2009
Today marks the start of National Chemistry Week, an ACS-sponsored event designed to help foster an interest and understanding of chemistry. This year's focus is on the elements, so I thought the best way to kick off National Chemistry Week would be to introduce the elements found in the human body. 99% of the human body is made up of just six elements.
clipped from jchemed.chem.wisc.edu What could be more central to the study of chemistry than the periodic table of the elements? It combines all of the known elements into a tabular form, arranged by atomic number, grouping elements together by similarities in their chemical properties. "Chemistry—It's Elemental" is exactly what this year's National Chemistry Week is celebrating—and it is no accident that this is the 140th anniversary of Mendeleev's periodic table.
Most of the human body is made up of water, H2O, with cells consisting of 65-90% water by weight. Therefore, it isn't surprising that most of a human body's mass is oxygen. Carbon, the basic unit for organic molecules, comes in second. 99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.