How many elements are on the periodic table?
The periodic table has 118 confirmed elements. The most recent four, nihonium, moscovium, tennessine and oganesson, were officially named in 2016.
About 90 elements occur naturally on Earth, from hydrogen to uranium, although some appear only in tiny traces. The rest have been made in laboratories, usually by smashing atoms together in particle accelerators. Many of these heavy elements exist for only fractions of a second before they decay.
Russian chemist Dmitri Mendeleev published the first widely recognized periodic table in 1869. He arranged elements by atomic weight and properties and left gaps for elements not yet discovered, correctly predicting what some of them would be like. Today the table is ordered by atomic number, the number of protons in each atom.
Will there be more?
Scientists are trying to make elements 119 and 120, which would start a new row of the table. The International Union of Pure and Applied Chemistry must confirm any discovery before it gets a name and symbol.
Did You Know?
Elements are often named after places and people. Americium, californium and nihonium (after Nihon, Japan) honor places, while einsteinium, curium and mendelevium honor famous scientists.