|Heidelberg—Robert Bunsen, Gustav Kirchhoff, Carl Setterberg elements|
- Robert Bunsen and Gustav Kirchhoff
- built a flame emission spectroscope in 1859
- and in 1860 discovered caesium,
- the first element discovered by spectroscope.
- The spectrographic analysis of mineral water
- presented two bright lines for caesium
- so they named it after the Latin word
- for the color of its lines, “deep blue.”
- After distilling forty tons of this water,
- they obtained seventeen grams of caesium oxide.
- In 1882, one of Bunsen’s students, Carl Setterberg,
- got pure caesium from electrolysis of caesium cyanide.
Atomic number 55
- Caesium formate for drilling fluids.
- Caesium atom transitions in atomic clocks.
- Caesium vapor to generate electricity from heat,
- to neutralize the space charge in vacuum tubes,
- and to emit light in magnetometers.
- Caesium in photoelectric cells.
- Caesium iodide and bromide in radiation detectors.
- Caesium nitrate in infrared flares.
- Radioactive caesium-137,
- seven-eighths gone in a lifetime,
- produced in nuclear power plants
- by decay of uranium to xenon to caesium,
- and we used to think
- we would live, it seemed, forever.