OCR B (Salters) Unit 2 Elements From The Sea

Notes made mainly using Chemical Ideas; have used the specification (included) to take relevant notes. Some bits are missing, either because I didn't want to revise them or they were too complex to type.

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  • Created by: Emily
  • Created on: 26-05-11 21:16

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Chemistry Of Natural Resources-Elements From The Sea



Formulae, equations and amount of substance

Use the concept of amount of substance to perform calculations involving: molecular formulae,
percentage yield, masses of reagants, volumes of gases and concentrations of solutions; write and
interpret any balanced chemical equations required, including ionic equations*

A…

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The sub-shells are themselves divided further into atomic orbitals: an s sub-shell always
contains one s atomic orbital; a p sub-shell always contains three p atomic orbitals; a d sub-shell
always contains five d atomic orbitals; an f sub-shell always contains seven f atomic orbitals.

The energy level of the…

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Metallic lattice-High melting point, insoluble in water, good conductor of electricity

Explain the term electronegativity; recall qualitatively the electronegativity trends in the Periodic
Table; use relative electronegativity values to predict bond polarity in a covalent bond; decide
where a molecule is polar or non-polar from its shape and the polarity…

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Atoms in elements are in oxidation state zero; in simple ions, the oxidation state is the same
as the charge on the ion. Since compounds have no overall charge, the oxidation states of all the
constituent elements must add up to zero.

F: -1
O: -2 (except in O² and…

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The group of an element refers to the number of outer shell electrons in an atom of
said element, which dictates how many electrons it will lose/gan when forming an
ion, and thus determining its charge
Recall the names and formulae of NO, SO², CO², OH, NH, HCO; write formulae…

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With more electrons in each molecule, the strength of the intermolecular bonds increases, accounting
for the change in physical state of the halogens.

Use given information to compare different methods of manufacturing chemicals industrially, in terms
of atom economy, percentage yield, batch versus continuous process, siting the plant, cost of…

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Bromine has a dense and choking vapour-the liquid produces painful sores if spilled on the
skin. Great care has to be taken when transporting bromine; most of it is carried in lead-lined steel
tanks, supported in strong metal frames-each tank holds several tonnes of the element. International
regulations control the…

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See above



Organic reactions

Describe in outline the preparation of a chloroalkane from an alcohol using HCl

Reacting an alcohol with the appropriate hydrogen halide can make a monosubstituted
halogenoalkane. For example, chloromethane can be made by reacting methanol with hydrogen
chloride. This reaction is an example of a substitution…

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Substitution reactions are typical of halogenoalkanes-for example, a substitution
reaction takes place between a halogenoalkane and hydroxide ions, in which the
halogenoalkane is hydrolysed to form an alcohol. For example, in bromobutane
(CH-CH-CH-CH-BR), the C-Br bond is polar, and the oxygen atom of the hydroxide
ion is negatively charged. The…

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The great strength of the C-F bond makes it very difficult to break, so fluoro compounds are
very unreactive. As you go down the group, the C-Hal bond gets weaker, so the compound becomes
more reactive. Bromo and iodo compounds are fairly reactive, which makes them useful as
intermediates in…

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