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The reactivity series is sometimes quoted in the strict reverse order of standard electrode potentials, when it is also known as the "electrochemical series". [8] The following list includes the metallic elements of the first six periods. It is mostly based on tables provided by NIST.
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
The General Certificate of Secondary Education (GCSE) is an academic qualification in a range of subjects taken in England, Wales, and Northern Ireland, having been introduced in September 1986 and its first exams taken in 1988.
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.
The chemical reactivity of halogen atoms depends on both their point of attachment to the lead and the nature of the halogen. Aromatic halogen groups are far less reactive than aliphatic halogen groups, which can exhibit considerable chemical reactivity. For aliphatic carbon-halogen bonds, the C-F bond is the strongest and usually less ...
This is because stronger bonds form between atoms towards the top of the reactivity series, and strong bonds are difficult to break. For example, copper is near the bottom of the reactivity series, and copper sulfate (CuSO 4 ), begins to decompose at about 200 °C (473 K; 392 °F), increasing rapidly at higher temperatures to about 560 °C (833 ...
The activity series for halogens is: [1] [2] [3] > > > Due to the free state nature of and , single displacement reactions are also redox reactions, involving the transfer of electrons from one reactant to another. [4]
In August 2018, Ofqual announced that it had intervened to adjust the GCSE Science grade boundaries for students who had taken the "higher tier" paper in its new double award science exams and performed poorly, due to an excessive number of students in danger of receiving a grade of "U" or "unclassified".