Devolution is the. a. passing of authority from the national government to the state and local levels. b. expansion of national authority that began in the 1930s. c. contraction of state authority and the expansion of local government authority.
Hello, There you go. The French chemist Paul-Emile Lecoq de Boisbaudran (1838â1912), who discovered it in 1875. Gallium (Latin Gallia meaning Gaul; also gallus, meaning rooster) was discovered spectroscopically by Lecoq de Boisbaudran in 1875 by its characteristic spectrum (two violet lines) in an examination of a zinc blende from the Pyrenees.
But instead of seeing this as a problem, Mendeleev thought it simply meant that the elements which belonged in the gaps had not yet been discovered. He was also able to work out the atomic mass of the missing elements, and so predict their properties. And when they were discovered, Mendeleev turned out to be right. For example, he predicted the properties of an undiscovered element that should fit below aluminium in his table. When this element, called gallium, was discovered in 1875, its properties were found to be close to Mendeleev's predictions.