1871 Predictions
The existence of an element between thorium and uranium was predicted by Mendeleev in 1871. In 1900 William Crookes isolated protactinium as a radioactive material from uranium which he could not identify. Different isotopes of protactinium were identified in Germany in 1913 and in 1918, but the name protactinium was not given until 1948. Note that since the 1950s thorium, uranium and protactinium have been classified as actinides, hence protactinium does not occupy the place of eka-tantalum in what is now called Group 5.
Read more about this topic: Mendeleev's Predicted Elements
Famous quotes containing the word predictions:
“The Brahmins say that in their books there are many predictions of times in which it will rain. But press those books as strongly as you can, you can not get out of them a drop of water. So you can not get out of all the books that contain the best precepts the smallest good deed.”
—Leo Tolstoy (1828–1910)