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Rubidium Rb
Where is rubidium used--or where does it impact our everyday lives?
Rubidium symbol Rb
Atomic number: 39 Atomic mass: 85.47
Solid at room temperature
Where on Periodic Table: Group 1, Period 5 an Alkali Metal
Melting point 39.3 oC (102.74 oF)
Boiling point 688 oC (1279.4 oF)
Density 1.53 g/mL
Reaction with air (O2)
4Rb + O2-->2Rb2O
Reaction/solubility in water
Rubidium metal reacts rapidly with water and forms rubidium hydroxide (RbOH) and hydrogen gas (H2). The reaction is very exothermic and due to its placement on the periodic table, it is slower than caesium (which is immediately below rubidium on the periodic table) but faster than that of potassium (which is immediately above rubidium).
2Rb + 2H2O --> 2RbOH + H2
Rubidium was considered to be relatively rare, but with location and extraction techniques it is the 16th most abundant element in the Earth’s crust.
Source: LANL.gov
Researcher: Mia G
The atomic clock whcih is the timekeeper for the US Master Clock is at the U.S. Naval Observatory is barely two miles from Tregaron.
Link to the US Naval Observatory atomic clock site
The elements involved are rubidium and cesium
There are 4 rubidium fountain clocks and 19 5071 cesium clocks at the US Naval Observatory as well as 22 hydrogen maser clocks.
Rubidium atoms oscillate at about 6.8 billion times per second, and their frequency and stability can be measured to a precision of fractions of a trillionth of a second. Go to the link to discover more about rubidium time keeping
With cesium, a second was defined as the duration of 9,192,631,770 cycles of microwave light absorbed or emitted by the hyperfine transition of cesium-133 atoms in their ground state undisturbed by external fields. This information is from http://tycho.usno.navy.mil/cesium.html Go straight to the link for more information.
Rubidium was discovered spectroscopically, where light is split into characteriastic wavelengths. Here Chemistry One students are studying the spectra of lights and elements.
WIS Photographer
