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Triple Award Science, commonly referred to as Triple Science, results in three separate GCSEs in Biology, Chemistry and Physics and provide the broadest coverage of the main three science subjects. The qualifications are offered by the five main awarding bodies in England; AQA , Edexcel , OCR , CIE and Eduqas .
Solid lithium oxide adopts an antifluorite structure with four-coordinated Li+ centers and eight-coordinated oxides. [4]The ground state gas phase Li 2 O molecule is linear with a bond length consistent with strong ionic bonding.
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.
As an example, electrolysis of acetic acid yields ethane and carbon dioxide: CH 3 COOH → CH 3 COO − → CH 3 COO· → CH 3 · + CO 2 2CH 3 · → CH 3 CH 3. Another example is the synthesis of 2,7-dimethyl-2,7-dinitrooctane from 4-methyl-4-nitrovaleric acid: [3] The Kolbe reaction has also been occasionally used in cross-coupling reactions.
In chemistry and manufacturing, electrolysis is a technique that uses direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction. Electrolysis is commercially important as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell .
In chemistry, a reactivity series (or reactivity series of elements) is an empirical, calculated, and structurally analytical progression [1] of a series of metals, arranged by their "reactivity" from highest to lowest.
Important examples of electrolysis are the decomposition of water into hydrogen and oxygen, and of bauxite into aluminium and other chemicals. Electroplating (e.g. of Copper, Silver, Nickel or Chromium) is done using an electrolytic cell. Electrolysis is a technique that uses a direct electric current (DC). [citation needed]
Considering the industrial production of hydrogen, and using current best processes for water electrolysis (PEM or alkaline electrolysis) which have an effective electrical efficiency of 70–80%, [68] [73] [74] producing 1 kg of hydrogen (which has a specific energy of 143 MJ/kg) requires 50–55 kW⋅h (180–200 MJ) of electricity.