Elements of the Periodic Table. Island of Stability. PBS Airdate: October 3, 2006 NEIL DEGRASSE TYSON: Okay, remember this thing? That mysterious chart of boxes from chemistry class? Of course; it's the periodic table. It lists all the known elements, like hydrogen, gold, calcium, aluminum and even, down here, Einsteinium. What makes an element unique is the number of protons each atom contains. The table starts up here, at one, and keeps going and going and going. Well, correspondent Carla Wohl has found some folks who spent their lives trying to do just that. CARLA WOHL: Every atom in the universe was born in fire: oxygen, iron, neon, copper, carbon, the fundamental building blocks that make up all matter, all things, were created with immense heat and pressure, by the big bang, stars, or sometimes by scientists like Ken Moody. KEN MOODY: I don't feel very stellar, I guess. CARLA WOHL: He does, however, rise before the sun each morning and gets to work by 5:00, seven days a week.
KEN MOODY: That's the way it is. KEN MOODY: Uh, Ruthenium. Dmitri Mendeleev: Great Minds. Mendeleev's Periodic Table. Ferocious Elements. Dynamic Periodic Table. Graphing the Periodic Table | Science. The periodic table organizes over 100 known elements into 18 columns and seven rows.
The columns are called groups (or families), and rows are called periods. The layout of the table—arranged by increasing atomic number (the number of protons in the nucleus)—shows trends and patterns within periods and groups, which can be used to predict the properties of an element given its place in the table. Trends in properties of the elements can be explained by electron configurations. According to the atomic model, electrons orbit the nucleus at specific levels, or shells. As atomic number increases, so does the number of electrons around the nucleus; in the table, each element has one more electron than the element preceding it. A number of other relationships can also be seen, including patterns in atomic radius, electronegativity, and ionization energy.
Electronegativity is the measure of an atom's ability to attract electrons in chemical bonds.