Average mass of an atom in unified atomic mass units (1 u is 1/12 of the mass of a carbon-12 atom). Accounts for the natural mix of the element’s isotopes.
Number of the vertical column, 1 to 18 in IUPAC numbering. Elements in a group share the same outer-shell layout, so their properties are alike.
Number of the horizontal row. Usually equal to the number of electron shells in the atom; palladium is the exception, with four shells in period 5.
The subshell (s, p, d or f) that receives the last electrons in the usual filling order; it divides the table into four blocks. Real atoms sometimes differ: lanthanum starts the f-block but has no f electrons.
[Ar] 4s² 3d¹⁰
How electrons are arranged in subshells. The bracket stands for the previous noble gas; the superscript is the number of electrons in a subshell.
2, 8, 18, 2
Number of electrons in each shell, from the nucleus outwards.
419.5 °C (692.68 K)
Temperature at which the solid turns liquid at standard pressure. Helium, carbon and arsenic do not melt at normal pressure: helium needs about 25 atm, carbon and arsenic turn straight into vapour.
907 °C (1,180 K)
Temperature at which the liquid boils at standard pressure. For carbon and arsenic, the temperature at which the solid turns straight into vapour (sublimation).
7.134 g/cm³
Mass of one cubic centimetre of the substance. For gases, at 0 °C and standard pressure.
1.65 Pauling
How strongly an atom pulls electrons towards itself in a chemical bond. On the Pauling scale it runs from 0.79 for caesium to 3.98 for fluorine.
9.394 eV
Energy needed to remove the most loosely bound electron from an atom. The lower it is, the more easily the element gives up an electron, which is typical of metals.
no stable negative ion
Energy released when a neutral atom gains an electron. Highest for the halogens. Noble gases, nitrogen and some metals form no stable negative ion.
122 pm
Half the length of a single covalent bond between two atoms of the element. It shows the size of an atom inside a molecule or crystal: 76 pm for carbon, 132 pm for iron.
+2
Charges the atom would have in its compounds if all its bonds were ionic; the main ones are listed.
Zinc (Zn) is a chemical element with atomic number 30. It sits in group 12 and period 4 of the periodic table, in the d-block. It is a transition metal. At room temperature it is a solid. Its standard atomic weight is 65.38.
Origin of the name
The name comes from the German Zink, first used for the metal by Paracelsus in the 16th century; it probably goes back to Zinke, ‘prong, tooth’. Zinc ores were used to make brass for many centuries before zinc itself was known. The metal was first produced in India, and in Europe Andreas Sigismund Marggraf obtained it in 1746 by heating zinc ore with charcoal.
Where is zinc found?
The main ore of zinc is sphalerite, a zinc sulfide, often found together with ores of lead and copper.
What is zinc used for?
The biggest use of zinc is galvanising: a coat of zinc protects iron and steel, such as nails, from rusting. Zinc also goes into batteries, into brass and into precisely cast small parts. Zinc oxide is used in paints, rubber, cosmetics and medicines, and zinc sulfide glows when struck by light or electrons, as in luminous dials and old television screens.
Interesting facts
Zinc was one of the metals in Alessandro Volta’s pile, the first electric battery.
Zinc is essential for living things: people and animals cannot grow properly without it.