What is metal?
Metal is a solid, glossy, and pliable material that conducts heat and electricity. It can present as a pure element, a mixture, or a compound. Examples of metals are iron, gold, bronze, steel, and polythiazyl. It has many uses in construction, manufacturing, and other industries.
What is a metal simple definition? Metal is a solid material that conducts heat and electricity as a pure element, mixture, or compound.
Other Definitions
Metal in chemistry: metal is an element that forms a positively charged ion, called a cation. When in a chemical reaction, a metal releases electrons to form metallic bonds with a negatively charged ion, called an anion. Examples of metals in chemistry are sodium, potassium, magnesium, and iron. Some common properties of metals include high melting and boiling points, ductility, and conductivity.
Metal in physics: metal is any material that can act as an electrical conductor at 0°K or absolute zero. At sufficiently high pressure, certain materials become metallic in nature. This includes other materials that are not usually considered metals. An example is iodine which becomes starts to become a conductor at 40 times atmospheric pressure.
Metal in astrophysics: metal is any element that is heavier than helium. The universe creates materials on stars that run fusion reactions continuously. Stars fuse hydrogen and helium into heavier elements starting with carbon, nitrogen, oxygen, and neon. In interstellar terms, any element heavier than helium is a metal element.
Types of metals
Ferrous and non-ferrous metals
Ferrous metals contain iron as their main component and are commonly used in construction and manufacturing. Because they contain iron, they are hard, malleable, ductile, magnetic, and good conductors. Examples are wrought iron, carbon steel, and stainless steel.
Non-ferrous metals do not contain iron. They are often used in industries such as aerospace and electronics, due to their high conductivity and resistance to corrosion. Examples are copper, aluminum, and titanium.
Metals in the periodic table
Alkali metals are elements in the periodic table’s Group 1. This includes the elements lithium, sodium, potassium, and others. They are very reactive, especially with water, and are never found in their elemental form in nature.
Alkaline earth metals are elements in Group 2. Under this group are beryllium, magnesium, calcium, and others. They are also reactive and not usually found in elemental form in nature.
Transition metals are a large group that includes iron, copper, nickel, gold, silver, zinc, and mercury. They are less reactive than alkali and alkaline earth metals, and many of them are commonly found in their elemental form. They have excellent heat and electric conductivity.
Post-transition metals follow the transition metals on the periodic table. They include elements like aluminum, gallium, indium, thallium, tin, and lead. They are generally softer and more reactive than the transition metals.
Lanthanides are the elements 57-71 on the periodic table also called "rare earth metals". They include elements like lanthanum, cerium, praseodymium, neodymium, and others.
Actinides are the elements 89-103 on the periodic table. They include elements like thorium, uranium, and plutonium, as well as several artificial elements. Most are highly radioactive.
Other types of metals
Noble metal such as gold, silver, copper, and mercury is almost impervious to corrosion and oxidation.
Precious metal is a noble metal that's scarce and has high economic value. Other precious metals are ruthenium, rhodium, palladium, osmium, and iridium.
Base metal is a common, inexpensive metal like copper, lead, and zinc.
A metal alloy is a mixture of two or more metals, or a metallic element and another chemical element, which is combined to enhance or alter the properties of the base pure metal. Examples include steel (iron and carbon), bronze (copper and tin), and brass (copper and zinc).
Heavy metal is a substance that has high density, atomic number, or atomic weight. In environmental science and toxicology, heavy metal is toxic even at low concentrations. Examples are mercury, cadmium, and arsenic.
Forms of metals
Simple forms
Metal can be shaped into a wide variety of forms due to their inherent properties like ductility and malleability.
The metal sheet is pressed and rolled metal into a thin, flat sheet. Sheets have many uses such as car bodies, roofing, and foils used for cooking.
Metal can be shaped into long, cylindrical metal rods or bars of various cross-sectional shapes. These are used in the construction and manufacturing process.
It can be shaped into hollow metal tubes or pipes. These are used in plumbing, the oil industry, and in building structures.
Thin metal wires are drawn out from ductile materials like copper, tungsten, and even gold for use in electrical wiring.
Some metals can be made into fine metal powder, often used in metallurgical processes like powder metallurgy or in applications like paint pigments.
Complex forms
Metals can be melted and poured into a mold, then solidified to produce a metal casting. This can create complex shapes that would be difficult or impossible to achieve with other shaping processes.
Metal can be heated until it's very pliable, then hammered or pressed into shape. Metal forging is often used to produce tools, weapons, or other items that need to be very strong.
Metal can be pushed or drawn through a die to create long objects with a constant cross-section. Different metal extrusions are used to produce rails or profiles for windows and doors.
Metal can be cut, drilled, turned, or otherwise machined into a wide variety of shapes. Machined metal can be a screw, bolt, or intricate metal part for engines or machines.
Interesting facts about metals
Metal on earth
The Earth's total mass is made up of a significant amount of metal, primarily found in the Earth's core and mantle.
- The Earth's core, which makes up about 31.5% of the Earth's mass, is primarily composed of iron and nickel.
- The mantle, which accounts for about 68.1% of Earth's mass, is primarily composed of silicate rocks, which are not metallic. However, it does contain some positive ions (such as iron and magnesium) as part of these silicate minerals.
- The Earth's crust accounts for less than 1% of the Earth's total mass. The crust is mostly made up of non-metallic elements (like oxygen and silicon), but also contains metals such as aluminum (the most abundant metal in the crust), iron, and smaller amounts of other metals.
Hardest and softest metal
The hardest metal is chromium, known for its high hardness level and its ability to resist tarnishing and corrosion.
Cesium is considered the softest metal, being alkali and located at the bottom of the periodic table. It has a Mohs hardness of 0.2, which means it's extremely soft and can be cut with a knife.
Densest and lightest metal
The densest metal is osmium, with a density of 22.59 grams per cubic centimeter. The least dense metal is lithium, with a density of 0.534 grams per cubic centimeter.
Liquid metal
At room temperature and atmospheric pressure, the only two metals that are in liquid form are mercury and gallium.
Mercury is the only metal that is liquid at standard room temperature (20-25 degrees Celsius). It's used in thermometers, barometers, and other scientific apparatuses.
Mercury becomes solid at temperatures below its freezing point of -38.83 degrees Celsius (-37.89 degrees Fahrenheit). Mercury transitions from its familiar liquid state to a solid state at this temperature and below.
Gallium is solid at room temperature but has a very low melting point of 29.76 degrees Celsius (85.57 degrees Fahrenheit). This means it will melt if held in your hand (body temperature is about 37 degrees Celsius).Highest & lowest melting point
The metal with the highest melting point is tungsten, which melts at approximately 3422 degrees Celsius (or 6192 degrees Fahrenheit). The metal with the lowest melting point is gallium, which melts at just 29.76 degrees Celsius (or 85.57 degrees Fahrenheit).
Highest & lowest boiling point
The metal with the highest boiling point is also tungsten, with a boiling point of approximately 5555 degrees Celsius (or 10031 degrees Fahrenheit). The metal with the lowest boiling point is mercury, which boils at 356.73 degrees Celsius (or 674.11 degrees Fahrenheit).
Polymer metals
Metal-polymer composites, often called "polymer metals" or "metal-polymer hybrids," combine metal elements and polymers. They aim to bring together the advantageous properties of both materials, such as metals' strength and thermal conductivityand the light weight, flexibility, and corrosion resistance of polymers.
A common example is metal-plated polymers, where a polymer substrate is coated with a thin layer of metal to enhance its properties. This is often used in electronics for things like connectors and switches, where the metal provides good electrical conductivity, and the polymer provides a lightweight, flexible structure.
Another example is metal-filled polymers, where small particles of metal are mixed into a polymer matrix. These can be used for various purposes, including electromagnetic shielding and antistatic materials.
There's also research into polymers that actually contain metal ions as part of their structure. These "metallopolymers" could potentially have unique properties, like improved conductivity or magnetism, though they're still a relatively new area of research.
Metallic but contains nonmetals
Polythiazyl, also known as (SN)x, is a type of polymer that is unusual because it is composed of only sulfur and nitrogen, which are nonmetals, however, it demonstrates metallic properties. Polythiazyl is interesting because it is a superconductor at very low temperatures. Specifically, it becomes superconducting below 0.26 Kelvin (-272.89 degrees Celsius, -459.20 degrees Fahrenheit).
Superconductors are materials that can conduct electricity without any resistance, meaning they don't lose any energy as heat. Most superconductors only have this property at extremely low temperatures, like polythiazyl. Other substances like polythiazyl are polyacetylene and graphite.Role of metals in investment
Metals are an important substance that has a wide range of applications in many industries. Their impact cannot be understated. In addition, metals also have a role in building and securing an investment portfolio. Precious metals are an important part of securing your retirement savings. Learn more about precious metals investing from the best gold IRA company, Augusta Precious Metals.