Search results
Results from the WOW.Com Content Network
Chlorine is a chemical element; it has symbol Cl and atomic number 17. ... Of these, the most commonly used in the laboratory are 36 Cl (t 1/2 = 3.0×10 5 y) ...
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
This is a list of chemical elements and their atomic properties, ordered by atomic number (Z).. Since valence electrons are not clearly defined for the d-block and f-block elements, there not being a clear point at which further ionisation becomes unprofitable, a purely formal definition as number of electrons in the outermost shell has been used.
Each distinct atomic number therefore corresponds to a class of atom: these classes are called the chemical elements. [5] The chemical elements are what the periodic table classifies and organizes. Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on.
Atomic Spectroscopy, by W.C. Martin and W.L. Wiese in Atomic, Molecular, & Optical Physics Handbook, ed. by G.W.F. Drake (AIP, Woodbury, NY, 1996) Chapter 10, pp. 135–153. This website is also cited in the CRC Handbook as source of Section 1, subsection Electron Configuration of Neutral Atoms in the Ground State.
Chlorine (17 Cl) has 25 isotopes, ranging from 28 Cl to 52 Cl, and two isomers, 34m Cl and 38m Cl. There are two stable isotopes, 35 Cl (75.8%) and 37 Cl (24.2%), giving chlorine a standard atomic weight of 35.45. The longest-lived radioactive isotope is 36 Cl, which has a half-life of 301,000 years. All other isotopes have half-lives under 1 ...
The atomic weight is a mass ratio, while the mass number is a counted number (and so an integer). This weighted average can be quite different from the near-integer values for individual isotopic masses. For instance, there are two main isotopes of chlorine: chlorine-35 and chlorine-37. In any given sample of chlorine that has not been ...
A period 3 element is one of the chemical elements in the third row (or period) of the periodic table of the chemical elements.The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases: a new row is begun when chemical behavior begins to repeat, meaning that elements with similar behavior fall into ...