Lithium (from λίθος) is a chemical element with the symbol Li and atomic number 3.- Lithium
The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr).- Alkali metal
It is a soft, silvery-white alkali metal.- Lithium
The lightest chemical elements are hydrogen and helium, both created by Big Bang nucleosynthesis during the first 20 minutes of the universe in a ratio of around 3:1 by mass (or 12:1 by number of atoms), along with tiny traces of the next two elements, lithium and beryllium.- Chemical element
The version of this classification used in the periodic tables presented here includes: actinides, alkali metals, alkaline earth metals, halogens, lanthanides, transition metals, post-transition metals, metalloids, reactive nonmetals, and noble gases.- Chemical element
5 related topics with Alpha
The periodic table, also known as the periodic table of the (chemical) elements, is a tabular display of the chemical elements.
Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on.
For example, the alkali metals in the first group all have one valence electron, and form a very homogeneous class of elements: they are all soft and reactive metals.
Potassium is a chemical element with the symbol K (from Neo-Latin kalium) and atomic number19.
In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts.
Potassium is the second least dense metal after lithium.
Sodium is a chemical element with the symbol Na (from Latin natrium) and atomic number 11.
Sodium is an alkali metal, being in group 1 of the periodic table.
Metallic sodium is generally less reactive than potassium and more reactive than lithium.
Domain coloring of a
Domain coloring of a
They are derived from the description by early spectroscopists of certain series of alkali metal spectroscopic lines as sharp, principal, diffuse, and fundamental.
The repeating periodicity of blocks of 2, 6, 10, and 14 elements within sections of the periodic table arises naturally from the total number of electrons that occupy a complete set of s, p, d, and f orbitals, respectively, though for higher values of quantum number n, particularly when the atom bears a positive charge, the energies of certain sub-shells become very similar and so the order in which they are said to be populated by electrons (e.g., Cr = [Ar]4s13d5 and Cr2+ = [Ar]3d4) can only be rationalized somewhat arbitrarily.
The outermost electrons of Li and Be respectively belong to the 2s subshell, and those of Na and Mg to the 3s subshell.
Caesium (IUPAC spelling ) (or cesium in American English) is a chemical element with the symbol Cs and atomic number 55.
It is a soft, silvery-golden alkali metal with a melting point of 28.5 C, which makes it one of only five elemental metals that are liquid at or near room temperature.
The only economically important ore for caesium is pollucite, which is found in a few places around the world in zoned pegmatites, associated with the more commercially important lithium minerals, lepidolite and petalite.