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Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...
Sodium is a metal where humans have discovered a great deal of its total roles in the body as well as being one of the only two alkali metals that play a major role in the bodily functions. It plays an important role in maintenance of the cell membrane potential and the electrochemical gradient in the body via the sodium-potassium pump and ...
Aluminum warrants special mention because it is the most abundant metal and the third most abundant element in the Earth's crust; [3] despite this, it is not essential for life. With this sole exception, the eight most highly abundant elements in the Earth's crust, making up over 90% of the crustal mass, [3] are also essential for life.
Element percentages in the human body. Trace metals are the metals subset of trace elements; that is, metals normally present in small but measurable amounts in animal and plant cells and tissues. Some of these trace metals are a necessary part of nutrition and physiology. Some biometals are trace metals.
The heaviness of naturally occurring metals such as gold, copper, and iron may have been noticed in prehistory and, in light of their malleability, led to the first attempts to craft metal ornaments, tools, and weapons. [36] In 1817 the German chemist Leopold Gmelin divided the elements into nonmetals, light metals, and heavy metals. [37]
Islamic Golden Age brass astrolabe Brass lectern with an eagle. Attributed to Aert van Tricht, Limburg (Netherlands), c. 1500.. Brass is an alloy of copper and zinc, in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic and chemical properties, [1] but copper typically has the larger proportion, generally 2 ⁄ 3 copper and 1 ⁄ 3 zinc.
Copper alloys are metal alloys that have copper as their principal component. They have high resistance against corrosion. Of the large number of different types, the best known traditional types are bronze, where tin is a significant addition, and brass, using zinc instead. Both of these are imprecise terms.
Many metals, particularly heavy metals are toxic, but some are essential, and some, such as bismuth, have a low toxicity. Metals in an oxidation state abnormal to the body may also become toxic: chromium(III) is an essential trace element, but chromium(VI) is a carcinogen. Only soluble metal-containing compounds are toxic.