Named after a Scottish village near where it was discovered in 1790, what soft metal element, symbol Sr, was used to make cathode ray TV tubes?
Alkaline earth metal the group to be named the "alkaline earth metals". The calcium compounds calcite and lime have been known and used since prehistoric times. The same is true for the beryllium compounds beryl and emerald. The other compounds of the alkaline earth metals were discovered starting in the early 15th century. The magnesium compound magnesium sulfate was first discovered in 1618 by a farmer at Epsom in England. Strontium carbonate was discovered in minerals in the Scottish village of Strontian in 1790. The last element is the least abundant: radioactive radium, which was extracted from uraninite in 1898. All elements except
Cathode ray charged particle, which was later named the "electron". Cathode ray tubes (CRTs) use a focused beam of electrons deflected by electric or magnetic fields to create the image on a television screen. Cathode rays are so named because they are emitted by the negative electrode, or cathode, in a vacuum tube. To release electrons into the tube, they first must be detached from the atoms of the cathode. In the early cold cathode vacuum tubes, called Crookes tubes, this was done by using a high electrical potential of thousands of volts between the anode and the cathode to ionize the