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Metals and nonmetals are two general classes of chemical elements that possess largely opposite physicochemical properties. Although the vast majority of the chemical elements on the periodic table are metallic elements, the non-metals possess a much richer and more diverse chemistry that has enabled the emergence of life on planet Earth. In fact, almost all the elements from which organic compounds are made are non-metals, and there are only a few very specific exceptions.
What are metals?
Metals are chemical elements made up of the s-block elements (with the exception of hydrogen), d-block (transition metals), f-block (rare earths or internal transition elements), and some of the heavier p-block elements. They are characterized by being, for the most part, dense solid elements with a high melting point, which conduct electricity and have a characteristic brightness.
These elements are ubiquitous in a large number of applications ranging from construction to the manufacture of bone implants thanks to their high mechanical resistance.
properties of metals
Some of the most outstanding properties of metals are:
- They are good electrical and thermal conductors.
- With the exception of mercury, all are solid under normal conditions of temperature and pressure.
- In general, they have high melting and boiling points.
- Some, like the alkali metals, are highly reactive and react violently with water, while others, like gold and other precious metals, are chemically inert.
- The atoms of metals are joined together by means of the metallic bond.
- They react with oxygen to form basic oxides.
- They are electropositive elements, which means that they tend to lose electrons and thus form positively charged ions or cations.
- Most are ductile, which means that they can be shaped and drawn into fine threads or wires without breaking.
- Many are malleable, that is, they can be stretched into thin plates or sheets.
What are non-metals?
Nonmetals are the elements in the upper right corner of the periodic table. They are the lightest elements of the pe block, they include the elements of the group of halogens, chalcogens, noble gases and others. As mentioned before, non-metals are the main components of organic matter, so they are essential elements for the existence of life.
Properties of non-metals
The properties of non-metals are very varied. In fact, they are much more varied than the properties of metals. While metals are almost all solids with a high melting point, among non-metals we can find elements with the lowest and highest melting points that exist, being able to be found in solid, liquid and gaseous states. For example, helium, a nonmetal, has the lowest boiling point, which is -272 °C, or 1 K; while, carbon graphite has a melting point of 3,550 °C and a boiling point of almost 5,000 °C.
However, some properties common to most non-metals can be mentioned:
- They are poor thermal and electrical conductors.
- They can be found in a solid, liquid and gaseous state under normal conditions of temperature and pressure.
- They tend to form covalent or polar covalent bonds when attached to each other.
- They form discrete molecules, although some can form covalent solids.
- They are electronegative elements, so they tend to capture electrons and thus become negatively charged ions or anions.
- They tend to react with oxygen to form acid oxides.
List of 5 metallic elements
Sodium (Na)
Sodium is element 11 on the periodic table. It is one of the most common alkali metals and is part of a wide variety of both organic and inorganic salts, including common table salt. It is a very active element that reacts violently with water to form sodium hydroxide, which is a strong base.
Iron (Fe)
It is element 26 on the periodic table and was one of the first metals discovered by man. It is the fourth most abundant element in the earth’s crust, but it is by far the most extracted or mined element (counting both metals and non-metals) and the metal most used by the human species. It is used in countless applications both in its pure state and mixed with other elements to form alloys with very different properties.
Aluminum (Al)
Aluminum is another of the metals we use in countless applications ranging from construction and electrical conduction to the manufacture of automobiles, airplanes, and food containers. It is the most abundant metal in the earth’s crust and has the atomic number 13.
Gold (Au)
Gold is one of the best known precious metals. It is a very little abundant element, making up only 0.0000004% of the Earth’s crust. Gold is a noble, very inert, stainless, very soft and malleable metal that has been used for thousands of years to make all kinds of fine jewelry. Today it is also used in the manufacture of electrical contacts in electronic equipment of all kinds.
Copper (Cu)
Copper is element number 29 on the periodic table. It is a transition metal with a characteristic reddish color and is one of the best known conductors of electricity and heat. Only silver surpasses it in electrical and thermal conductivity, but its lower price makes it one of the most ubiquitous materials in all types of electrical circuits.
List of 5 non-metallic elements
Carbon (C)
Carbon is the basic element of life. It represents the main element of all organic chemical compounds and forms the main chain or skeleton of all this class of compounds. It occurs in several naturally occurring allotropes with unique and radically different properties. While graphite is a very soft black solid and a good conductor of electricity, diamond, the other most common form of elemental carbon, consists of solid covalent crystals that are the hardest known material; These crystals are also exceptional thermal and electrical insulators.
Nitrogen (N)
Elemental nitrogen is a gas formed by diatomic molecules (N 2 ) and is the main component of the Earth’s atmosphere. It is an essential element for life: together with carbon, hydrogen and oxygen, it forms the components of DNA, RNA and the amino acids that make up proteins. It is element 7 of the periodic table and is the first element of group 15.
Oxygen (O)
Located just before nitrogen and with atomic number 6, oxygen is the most abundant element in the earth’s crust. In fact, oxygen alone makes up almost half of the mass of the earth’s crust, since it is associated with almost all the other elements that make it up. This is due to its unique ability to form compounds with both metals and non-metals.
Hydrogen (H)
Hydrogen is the lightest element on the periodic table. It has the atomic number 1 and is made up of a single proton surrounded by a single electron. In its natural state, it is in the form of a diatomic gas that burns in the presence of oxygen to form water. The uses and applications of hydrogen are very varied and cover many industries. These applications include its use as a chemical reagent in the catalytic hydrogenation of hydrocarbons and other unsaturated organic compounds, as well as its use as a fuel in electric cars and as a propellant in some types of space rockets.
Fluorine (F)
Fluorine is characterized as the most electronegative element in the periodic table. It is element 9 on the periodic table and the lightest of the halogen group. In its elemental state, it is an extremely irritating and poisonous green to yellow diatomic gas. Furthermore, it is a highly reactive gas, capable of oxidizing a wide variety of chemical compounds.
How to recognize if an element is a metal or a non-metal?
The easiest way to identify whether an element is metallic or non-metallic is to locate it on the periodic table. If they are in block s, dof, then it is sure to be a metal. However, a question may arise if the element is in the p-block, since this block includes both non-metals and some metals.
The easiest way to distinguish one from the other is by learning the names of the elements that separate metals from non-metals, which are the metalloids or semi-metals. These elements form something similar to a diagonal that clearly separates metals from non-metals and are:
- Boron
- Silicon
- Germanium
- Arsenic
- Antimony
- telluride
- Polonium
Anything below or to the left of these seven elements will be a metal, while those to the right or above are nonmetals.
Finally, it should be noted that the heaviest elements of the p block, that is, nihonium (Nh), flerovium (Fl), muscovium (Mc), livermorium (Lv), teneso (Ts) and oganeson (Og ), are synthetic elements whose physical and chemical properties are practically unknown, so they cannot be classified as metals, non-metals, or metalloids.
References
Chang, R. (2021). Chemistry (11th ed .). MCGRAW HILL EDUCATION.
Editors of the encyclopedia. (nd). Abundance of the elements . Encyclopedia Britannica. https://www.britannica.com/science/abundance-of-the-elements
Libretexts. (2021, February 3). Solid Metallic Elements . Chemistry LibreTexts. https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Map%3A_Inorganic_Chemistry_(Housecroft)/06%3A_Structures_and_energetics_of_metallic_and_ionic_solids/6.03%3A_The_Packing_of_Spheres_Model_Applied_to_the_Structures_of _Elements/6.3C%3A_Solid_Metallic_Elements
Monroe Engineering. (2019, November 14). How Metal Elements Differ From Nonmetal Elements . Monroe Engineering. https://monroeengineering.com/blog/how-metal-elements-differ-from-nonmetal-elements/ QuestTech. (2021, April 22).
Best Conductor of Electricity: Choosing the Right Metals | Quest Tech . Quest-Tech Precision Inc. https://questtech.ca/blog/best-conductor-electricity/
