Cadmium

Cadmium, Cd, is a transition metallic element found in Group IIb of the periodic table.

Atomic Number : 48
Relative Atomic Mass : 112.40 Cadmium and its compounds are highly toxic and must be handled with great care.

Discovery

Cadmium was discovered by F Stromeyer in 1817AD.

Occurrence

Cadmium is often found in association with Zinc ores.
Cadmium is also found in Greenocklite, CdS.

Extraction

Cadmium is separated by repeated distillation from the zinc which is produced from its ore by distillation.
Cadmium is also produced by precipitation from the liquors produced during the electrolytic refining of zinc.

Preparation

Manufacture

Properties

Cadmium is a soft white ductile metal which melts at 320 degC.
Cadmium oxidises slowly in moist air, but burns when heated.
Cadmium is similar to zinc in many of its chemical properties.

Reactions

Cadmium is closely resembles zinc in its chemical properties.

Uses

Cadmium is used

in electroplating,
in bearing alloys which great resistance to fatigue and low coefficients of friction,
in electronics, where cadmium sulphide is a photosensitive material,
in the green and blue phosphors in colour TV tubes,
in the Weston standard voltaic reference cell, and
in alloys, including Wood's Alloy contains bismuth, lead, tin, and cadmium, in the ratio 4:2:1:1.

Start of Hypertext .... Elements .... Compounds .... Index

Hypertext Copyright (c) 2000 Donal O'Leary. All Rights Reserved.