The word ‘atom’ comes from the Greek word atomos. Everything in the world, as you may already know, is made up of these tiny speckles of energy and forces.
There’s a total of 118 elements on Earth. 90 are found naturally occurring, while 28 are only synthesized by researchers. Each of these elements is identified by a one or two letter symbol, with the first being uppercase and the second being lowercase.
These elements are placed into an organized system known as the table of elements.
Some elements have similar properties, their position on this table can help tell us about their properties. The elements are divided into three categories:
- Metals: Shiny and conduct electricity. They’re ductile, meaning they can be stretched into wires and malleable, meaning they can be formed into shapes.
- Metalloids: these have properties between metals and nonmetals.
- Nonmetals: poor at conducting heat and electricity.
Elements in the Human Body
96% of the mass of a human body is made up of four elements:
Hydrogen and Oxygen make up H20. H20 makes up more than 70% of the human body making water the most prevalent substance in the human body. Carbon, Oxygen, and Hydrogen make up the four main types of biomolecules; proteins, lipids, carbohydrates, and nucleotides. Nitrogen is found in proteins and nucleic acids.
Some elements are found as minerals in our bodies. They make up 0.1% to 2% of the body mass. In our bodily fluids, we can find Sodium, Potassium, and Chlorine. In proteins found in muscle tissue, we have Magnesium and Sulfur. In our teeth and bones, we can find Calcium and Phosphorus.
There are also trace amounts of other elements found in our bodies. In order to consider something ‘trace’, it needs to only make up o.1% of the mass. There’s 15mg or less of each of them, they range from Iron to zinc to Arsenic and Chromium.
- Iron is used in the protein hemoglobin to support the transport of oxygen throughout the body in the blood.
- Zinc is needed for the proper function of certain enzymes found in the liver and kidneys.
- Iodine is needed for the thyroid gland to function properly.
The atoms can connect to each other. They do so to form compounds. Some compounds can be 1 to 1 ratios such as NaCl, or Sodium Chloride also known as table salt. Most, though, are not so simple. H2O, or water, is a 2 to 1 ratio. This means there are two Hydrogen atoms for every Oxygen atom in the compound. These formations can be illustrated as ball-and-stick representations.
Above is an illustration of H2O as a ball-and-stick figure. The red ball representing the lone Oxygen atom, while the two blue balls are Hydrogen.