Comparison of copper and aluminum properties

Comparison of copper and aluminum properties

Copper is one of the earliest metal elements used by humans. Copper is purple red in color, high thermal conductivity and electrical conductivity, and is a good conductor; It is not oxidized in dry air, and patina will be formed in humid air containing CO2; It reacts slowly with alkaline solutions, but easily forms complexes with ammonia; The standard electrode potential is +0.337V, which cannot replace hydrogen in acid, but is soluble in oxidizing acids, and the electrochemical equivalent of divalent copper is 0.0003294g/C (coulomb). The extraction, processing, recycling and reuse of copper is not difficult, so from the primitive society to the prosperity of civilization and the high development of science and technology today, copper products have always accompanied mankind and made significant contributions to human progress.

Aluminum is a relatively young metal element. In 1746, German scientist J.H. Pett made alumina from alum. In 1807, the British chemist H. Davy tried to electrolyze molten alumina to obtain aluminum, and the following year named the intended metal Alumium, later changed to Aluminium, that is, aluminum. In 1825, Danish chemist H.C. Oersted reduced anhydrous alumina with potassium amalgam to obtain several milligrams of aluminum. In 1827, the German scientist F. Waller Wohler) reduced alumina with potassium to obtain a small amount of aluminum. In 1854, the French scientist S.C. Deville) uses sodium to reduce NaAlCl4 with salt to obtain aluminum, and produces some royal items such as helmets, cutlery and toys, which are expensive and more expensive than gold. In 1884, the total production of aluminum in the United States was 56.7kg. In 1886, American college student Hall and French college student Heroult invented the cryolite-alumina salt electrolytic aluminum smelting method almost simultaneously, announcing the birth of the industrial extraction process of aluminum, and they obtained invention patents in the United States and France respectively.