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GCSE Bitesize was launched in January 1998, covering seven subjects. For each subject, a one- or two-hour long TV programme would be broadcast overnight in the BBC Learning Zone block, and supporting material was available in books and on the BBC website. At the time, only around 9% of UK households had access to the internet at home.
Late transition metals are on the right side of the d-block, from group 8 to 11 (or 12, if they are counted as transition metals). In an alternative three-way scheme, groups 3, 4, and 5 are classified as early transition metals, 6, 7, and 8 are classified as middle transition metals, and 9, 10, and 11 (and sometimes group 12) are classified as ...
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
In 1860, the unexpected appearance of sky-blue and dark red was observed in spectral emissions by Robert Bunsen and Gustav Kirchhoff, leading to the discovery of two alkali metals, caesium and rubidium (dark red). [4] [1] Today, this low-cost method is used in secondary education to teach students to detect metals in samples qualitatively. [2]
Key Stage 3 (commonly abbreviated as KS3) is the legal term for the three years of schooling in maintained schools in England and Wales normally known as Year 7, Year 8 and Year 9, when pupils are aged between 11 and 14. In Northern Ireland the term also refers to the first three years of secondary education.
Native metals were prehistoric man's only access to metal, since the process of extracting metals from their ores is thought to have been discovered around 6500 BC. However, native metals could be found only in impractically small amounts, so while copper and iron were known well before the Copper Age and Iron Age , they did not have a large ...
Nonmetals show more variability in their properties than do metals. [1] Metalloids are included here since they behave predominately as chemically weak nonmetals.. Physically, they nearly all exist as diatomic or monatomic gases, or polyatomic solids having more substantial (open-packed) forms and relatively small atomic radii, unlike metals, which are nearly all solid and close-packed, and ...
In metallurgy, non-ferrous metals are metals or alloys that do not contain iron (allotropes of iron, ferrite, and so on) in appreciable amounts.. Generally more costly than ferrous metals, non-ferrous metals are used because of desirable properties such as low weight (e.g. aluminium), higher conductivity (e.g. copper), [1] non-magnetic properties or resistance to corrosion (e.g. zinc). [2]