Definition of motor for English Language Learners : of, relating to, used in, or involving a vehicle that is powered by a motor (such as a car or motorcycle) : having a motor
Ancient Greeks and Romans used aluminum salts for dressing wounds. However, aluminum metal was not isolated until the 19th century. Danish chemist Hans Christian Ãrsted first produced aluminum in 1825 by reacting aluminum chloride with potassium amalgam. Therefore, Ãrsted is considered to be the discoverer of Aluminum.
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.e 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.