Ask Me EverythingC

Where do metals come from?

strange metal because it is a liquid at room temperaturę. It has to be cooled to -38°F (-39°C) before it becomes solid

Metals are part of the rocks that form our planet—they are all around us in the solid bedrock, scattered Stones, and soft soil. Yet most of these metals dorYt look like the tough, shiny materials we are used to because they have been transformed by Chemical reactions with other elements.

FAST FACTS

Metals and minerals

01: All pure metals aie elements, which means that they contain just one type of atom. Three ąuarters of the 94 elements that occur naturally on Earth are metals.

02: Most pure metals

naturally react with other elements to form the Chemical compounds that we cali minerals.

03: The most familiar of these is iron oxide, a compound of iron and oxygen that we know as rust.

04: Iron oxide doesn’t look like metallic iron. Yet if it is heated with something called a reducing agent, this soaks up the oxygen and turns the oxide into pure metal.

05: The most common metals are produced in a similar way, from oxides and other compounds known as metal ores.

What is so special about metals?

■ Nearly all pure, refined metals are dense, opaque, shiny solids. Most are quite hard, but some are surprisingly soft.

♦ Many metals are extremely strong for their weight and can carry heavy loads and resist impacts.

# Metals can be easily worked or formed into shapes without cracking or crumbling, especially when hot.

Most metals are good conductors of electricity.

This makes them essential to modern technology.

Metal ores

Tell me morę: precious metals

■    Precious metals such as silver and gold boil up from Earth’s interior wherever there are volcanoes and hot springs. The hot water deposits the metals in cracks

in the rock called hydrothermal veins.

■    The most precious metals such as gold and platinum do not react easily with other elements to form compound minerals.

This means that they are found as veins and nuggets of pure metal.

■    Nonreactive precious metals do not oxidize (react with oxygen) in air, which is why gold always stays shiny.

I don t I believe it ■

Iron

The most important iron ore is hematite, or iron oxide (rust). It often occurs in rounded, rusty-looking nodules that feel very heavy when you pick them up.

Aluminum

This extremely common metal is found in morę than 270 different minerals. It is most easily extracted from a sedimentary rock called bauxite.

Copper

Some copper is found in pure form, but most is obtained from a brassy and metallic compound of iron, sulfur, and copper called chalcopyrite.

Tin

The primary ore of tin is cassiterite. This oxide, a compound of tin and oxygen, is usually found in regions where local rock has been heated by molten magma.

Some metals are so reactive that they cannot exist in pure form on Earth. When iron reacts with oxygen, it turns to rust, but when potassium meets oxygen, it bursts into fiames.

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