A type of heat treatment applied to metals to change their physical properties. The metal is heated to, and held at, an appropriate temperature before being cooled at a suitable rate to produce the desired grain structure. Annealing is most commonly used to remove the stresses that have arisen during rolling, to increase the softness
A type of organic hydrocarbon containing one or more alkyl groups substituted onto a benzene ring. Methylbenzene (C₆H₅CH₃) and 1,3-dimethylbenzene are simple examples. Alkylbenzenes can be made by a Friedel- Crafts reaction or by the Fittig reaction. Industrially, large quantities of methylbenzene are made by the hydroforming of crude oil. Substitution of alkylbenzenes can occur
alkali metals (group 1 elements) A group of soft reactive metals, each represent in the start of a new period in the periodic table and having an electronic configuration consisting of a rare-gas structure plus one outer electron. The alkali metals are lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr).