Ever noticed the bright colored fireworks in the 4th of July night sky? Maybe you have wondered where the pretty reds and purples come from.
Read on in this lesson to discover what role rubidium plays.
What is Rubidium?
Rubidium is a chemical element of group 1 (the first column on the periodic table) with the abbreviation Rb and atomic number 37. As a member of the alkali metals, rubidium has an oxidation state of +1.
It’s a silvery-metallic metal that has an atomic mass of about 86 grams per mole.
One very important fact that should be noted about the alkali metals is that they are very reactive and do not occur freely in nature. In fact, group 1 is so highly reactive that these metals react violently in both air and water. Rubidium is no exception to this property and can catch fire spontaneously when in contact with air, in addition to reacting violently with water.Because of the presence of only one electron in its outer shell, rubidium can readily lose this electron through ionic bonding. In fact, rubidium is one of the most electropositive elements on the periodic table, meaning that it easily loses it electrons.
Ionic bonding occurs when another element forms a compound by taking this electron away completely.As a group 1 metal, rubidium is much softer and more malleable as compared to most other metals. Rubidium is a very good conductor of both electricity and heat.
Uses of Rubidium
One of the main uses of rubidium is in the production of the beautiful purples that are seen in fireworks. Rubidium’s name comes from the Latin rubidus, meaning dark red. (This is due to the dark red lines that identify the element when using a spectroscope). So when you look up into the night sky and see the beautiful dark red and purple fireworks, think about rubidium; it is probably responsible for the colors you see!Another very cool and frequently used application for rubidium is its role as a species for laser cooling.
This is an application that requires that rubidium be in the vapor phase in an attempt to cool the atoms with a laser down to absolute zero. Absolute zero is the temperature at which all motion stops, and scientist use rubidium atoms in an attempt to achieve this goal. That is pretty cool!Yet another application for rubidium is in the precision timing in atomic clocks.
Rubidium atomic clocks can be thought of as one of the simplest of atomic clocks and are highly accurate.
Other Rubidium Facts
Rubidium was discovered in 1861 by German chemists Robert Bunsen and Gustav Kirchhoff by a newly developed method of flame spectroscopy while examining the mineral lepidolite. Unlike most metals, rubidium has a relatively low melting point of 39 degrees Celsius (or about 103 degrees Fahrenheit). However, the temperature at which this metal boils is quite high at 1270 degrees Fahrenheit.Moreover, there are at least 24 known isotopes of rubidium. That means that there exists at least 24 different variants of this metal, some of which are radioactive. Yet, research continues, so in the future there may be more isotopes of this element discovered.
However, naturally occurring rubidium consists of just two isotopes that are present in about a 30/70 split to each other.
Rubidium is a member of the group 1 elements known as alkali metals. It is the second most electropositive element on the periodic table, so it very easily gives up its one electron to form ionic bonds. Also, this metal reacts very violently in the presence of air and water. Rubidium is often used to color fireworks purple and in accurate time keeping with atomic clocks.