Alkali metal compounds have been known since antiquity. In 1807, Sir Humphry Davy surprised everyone by electrolytically preparing (and naming) potassium and sodium metals. In 1808, he noted their interaction with ammonia, which, 100 years later, was attributed to solvated electrons.

Group 1A (or IA) of the periodic table are the alkali metals: hydrogen (H), lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). These are (except for hydrogen) soft, shiny, low-melting, highly reactive metals, which tarnish when exposed to air.

Calcium is an alkaline earth metal. To form cations with a 2+ charge, all the alkaline earth metals readily lose their two outermost electrons. As an alkaline earth metal, when exposed to sunlight, calcium is a reactive metal forming a dark oxide-nitride film.

Lithium is a soft, silvery-white, metal that heads group 1, the alkali metals group, of the periodic table of the elements.

Alkali Metals are very reactive. They have low melting points and are soft enough to be cut with a knife. Potassium and sodium are two alkali metals. This group includes iron, gold, silver, chromium, nickel, and copper, some of which are also noble metals.

Copper metal does occur naturally, but by far the greatest source is in minerals such as chalcopyrite and bornite. Copper is obtained from these ores and minerals by smelting, leaching and electrolysis. The major copper-producing countries are Chile, Peru and China.

Properties of metals

• high melting points.
• good conductors of electricity.
• good conductors of heat.
• high density.
• malleable.
• ductile.

Appearance and Hardness of materials

List of Metals

Calcium (Ca) is an active metal and react with water at room temperature. Such metals are stored in kerosene. Calcium is an alkaline earth metal having atomic number 20.

Germanium (Ge), a chemical element between silicon and tin in Group 14 (IVa) of the periodic table, a silvery-gray metalloid, intermediate in properties between the metals and the nonmetals.

Carbon is a solid non-metal element. Pure carbon can exist in very different forms. The most common two are diamond and graphite.

The largest use of germanium is in the semiconductor industry. When doped with small amounts of arsenic, gallium, indium, antimony or phosphorus, germanium is used to make transistors for use in electronic devices. Germanium is also used to create alloys and as a phosphor in fluorescent lamps.

Germanium is not found as the free element in nature. Germanium is found in germanite, argyrodite, and some zinc ores. It is also present in coal and its presence in coal insures reserves for many years.

Winkler named the element after his country, Germany. Today, germanium is mined primarily from sphalerite (the primary ore of zinc), though germanium is also recovered commercially from silver, lead, and copper ores. Elemental germanium is used as a semiconductor in transistors and various other electronic devices.

Germanium is not an essential element. Its acute toxicity is low. However, at least 31 reported human cases linked prolonged intake of germanium products with renal failure and even death. Signs of kidney dysfunction, kidney tubular degeneration, and germanium accumulation were observed.

There have been claims that germanium may be beneficial for health, including improving the immune system, oxygen supply in the body, and destroying free radicals. According to Healthline, germanium has also been considered to be beneficial in treating allergies, asthma, arthritis, HIV/AIDS and various forms of cancer.

Germanium and kidney damage Germanium can break down your kidney tissue, causing kidney damage. In some cases, germanium can even cause chronic kidney failure and death.

Route of Entry: Skin Contact Skin Absorption Eye Contact Inhalation Ingestion Germanium metal is relatively non-toxic by all routes of exposure, particularly in massive forms.

Germanium is a naturally occurring element. Trace amounts can be found in foods such as shiitake mushrooms, garlic, tuna, and tomato juice. However, it is not an essential nutrient for human health. Germanium was considered by some as an elixir in the 1970s and ’80s for diseases such as cancer and AIDS.