In chemistry, an element is a building block of matter that cannot be broken into smaller pieces using any chemical means. Each element consists of atoms having a unique atomic number (number of protons in its nucleus), element symbol, and name. There are 118 elements known at present, although more may be synthesized in the future. Here are examples of elements, as well as their symbols, atomic numbers, and uses.
20 Examples of Elements
Here are 20 examples of elements. These are the first 20 elements, listed by atomic number, name, symbol, and use.
- Hydrogen (H): Most of the universe consists of hydrogen. It is a fuel and occurs in many compounds, such as water and hydrogen peroxide.
- Helium (He): Helium is a monatomic gas. It is used in cryogenics, balloons, and as an inert atmosphere.
- Lithium (Li): Lithium is a light, reactive metal. Uses include batteries, glass, ceramics, drugs, and lubricants.
- Beryllium (Be): Beryllium is a lightweight metal used in aircraft and spacecraft components. It is an important alloying agent.
- Boron (B): Boron is a metalloid found in minerals. It is an additive in fiberglass and finds use in borosilicate glass and ceramics.
- Carbon (C): All organic molecules contain carbon. Graphite and diamond are both pure carbon. Its compounds include plastics, carbon dioxide, and carbon monoxide.
- Nitrogen (N): Nitrogen is one of the elements essential for life. It occurs in nucleic acids, proteins, and energy transfer molecules. It finds use in ammonia, nitric acid, explosives, and propellants.
- Oxygen (O): Oxygen is essential for life. It occurs in organic molecules and many other important molecules, such as water, hydrogen peroxide, and ozone.
- Fluorine (F): Fluorine is a halogen used in fluoride toothpaste, Teflon, and aluminum refining.
- Neon (Ne): Neon is a monatomic gas, best known for its glow in neon lights and red helium-neon lasers.
- Sodium (Na): Sodium is an important electrolyte in living organisms. It is a highly reactive alkali metal that forms many compounds and minerals, including sodium chloride, feldspar, and sodalite.
- Magnesium (Mg): Magnesium is essential for life, primarily for enzyme function. It is an important structural metal. Its compounds find use in antacids and laxatives.
- Aluminum (Al): Aluminum is an important metal in everyday life, used in packaging, aviation, and construction.
- Silicon (Si): Silicon is a metalloid which is an important semiconductor. Electronics rely on the doped element. Its compounds find use in cement, glass, ceramics, and silicones.
- Phosphorus (P): Phosphorus is a key component of DNA, RNA, other organic molecules, and bones. It finds use in fertilizers, pesticides, and detergents.
- Sulfur (S): Sulfur is a nonmetallic element that is essential for life. It occurs in matches, insecticides, sulfuric acid, and fungicides.
- Chlorine (Cl): Chlorine is a halogen that is essential as an electrolyte in living organisms. It finds use in bleach and many compounds, including table salt.
- Argon (Ar): Argon is the most abundant noble gas in air. It finds use as an inert gas and in fluorescent lighting.
- Potassium (K): Potassium is an essential nutrient. Its compounds find use in fertilizer, food additives, drugs, and soap.
- Calcium (Ca): Calcium is essential for muscles, nerves, and the skeleton. The element and its compounds are used in steel and other alloys, pharmaceuticals, leavening agents, and resins.
About the Elements
Atomic Number
The periodic table lists elements in order of increasing atomic number. So, hydrogen is the first element, with atomic number 1. Oganesson is the last element, with atomic number 118. The groups (columns) and periods (rows) of the table organize elements according to recurring properties or periodic table trends.
Atoms with the same atomic number as each other are the same element, even if they have differing numbers of electrons (ions) or neutrons (isotopes).
Element Names
Elements are named for a person, place, property, mineral, or mythological figure. In English, element names are not proper nouns. That is, the first letter of the name is not capitalized unless it begins a sentence or list. By convention, halogen element names end with -ine and noble gas names end with -on. Many element names end with -ium, but it is not a requirement for any group.
Element Symbols
Element symbols are one- or two-letter abbreviations for element names. The first letter is capitalized, while the second letter is not. Notice that most of the time, the element symbol corresponds to its name. There are exceptions, such as K for potassium, Au for gold, and Pb for lead. In these cases, people knew the elements by other names before scientists agreed on an international naming system. These symbols reference the old names. For example, K is for kalium, Au is for aurum, and Pb is for plumbum.
References
- Ball, P. (2004). The Elements: A Very Short Introduction. Oxford University Press. ISBN 978-0-19-284099-8.
- Emsley, J. (2003). Nature’s Building Blocks: An A–Z Guide to the Elements. Oxford University Press. ISBN 978-0-19-850340-8.
- Gray, T. (2009). The Elements: A Visual Exploration of Every Known Atom in the Universe. Black Dog & Leventhal Publishers Inc. ISBN 978-1-57912-814-2.
- IUPAC (1997). “Chemical element”. Compendium of Chemical Terminology (the “Gold Book”) (2nd ed.). Blackwell Scientific. doi:10.1351/goldbook.C01022