There are 118 discovered chemical elements. Chemical elements are classified by the number of protons in their nucleus (something also called the "atomic number"). The atom has a nucleus, where the protons and electrons are, and a cloud of electrons.
Untriseptium (/ˌuːntraɪˈsɛptiəm/), also called eka-dubnium or element 137, is a possible chemical element which has not been synthesized.
Unbihexium (pronounced /ˌʌnbɪˈhɛksiəm/) is an unsynthesized chemical element with atomic number 126 and symbol Ubh.
The element which comes on 128 number is Trititanium (Tt).
Einsteinium - Element information, properties and uses | Periodic Table.
Darmstadtium - Element information, properties and uses | Periodic Table.
Untrioctium (pronounced /ˌʌntraɪˈɒktiəm/) is an unsynthesized chemical element with atomic number 138 and symbol Uto.
Unbibium, also known as element 122 or eka-thorium, is the hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122.
Untripentium, Utp, is the temporary name for element 135.
Ununennium, also known as eka-francium or element 119, is the hypothetical chemical element with symbol Uue and atomic number 119. Ununennium and Uue are the temporary systematic IUPAC name and symbol respectively, which are used until the element is discovered, confirmed, and a permanent name is decided upon.
Since element 123 is unknown, it has no biological role.
Unbipentium is a hypothetical (theoretical or imagined) element of the periodic table. It is also known as eka-neptunium. The atomic number of this element is 125. It has the symbol Ubp.
Astatine is the rarest naturally occurring element.
Although there are elements we have not yet created or found in nature, scientists already know what they will be and can predict their properties. For example, element 125 has not been observed, but when it is, it will appear in a new row of the periodic table as a transition metal.
Astatine is therefore the rarest element in the periodic table because it's the hardest to produce. So hard to produce, in fact, that the scientists who first created it in 1939 couldn't detect its existence directly and had to resort to a trick.
A synthetic element is one of 24 known chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made".
Livermorium. Pronunciation. /ˌlɪvərˈmɔːriəm/ (LIV-ər-MOR-ee-əm)
Sitting towards the end of the lanthanides, the floating strip of elements on the periodic table that squeezes between barium and lutetium, thulium has atomic number 69. It's one of the rare earths, elements that are largely misnamed as they are quite common.
Untribium, Utb, is the temporary name for element 132.
Indium - Element information, properties and uses | Periodic Table.
To discover element 119 using a calcium-48 beam, researchers would need a target made of einsteinium (element 99) which is even rarer than californium and berkelium. “We can't make enough einsteinium,” says Oak Ridge physicist James Roberto. Scientists need a new approach.
Uranium was discovered in 1789 by German chemist Martin Heinrich Klaproth. It is the heaviest naturally occurring element in the universe and is naturally radioactive. Its nucleus is unstable, so the element is in a constant state of decay, seeking a more stable arrangement.
This unknown element 119 would be in main group 1A (group 1) and located directly below francium (Fr). The unknown element of atomic number 120 would then immediately follow 119. Element 120 would be located in main group 2A (group 2, alkaline earth metal), directly below radium (Ra).
Element 120 is expected to be a typical alkaline-earth element.
Lanthanum - Element information, properties and uses | Periodic Table.