Search results
Results from the WOW.Com Content Network
AQA Education, [1] trading as AQA (formerly the Assessment and Qualifications Alliance), is an awarding body in England, Wales and Northern Ireland. It compiles specifications and holds examinations in various subjects at GCSE, AS and A Level and offers vocational qualifications. AQA is a registered charity and independent of the government.
In addition to specifications for each chemical, Reagent Chemicals provides detailed methods for determining how to measure the properties and impurities listed in the specifications. Included are detailed explanations for numerous common analytical methods such as gas , liquid , ion , and headspace chromatography , atomic absorption ...
A material property is an intensive property of a material, i.e., a physical property or chemical property that does not depend on the amount of the material. These quantitative properties may be used as a metric by which the benefits of one material versus another can be compared, thereby aiding in materials selection.
An example SDS, including guidance for handling a hazardous substance and information on its composition and properties. A safety data sheet (SDS), [1] material safety data sheet (MSDS), or product safety data sheet (PSDS) is a document that lists information relating to occupational safety and health for the use of various substances and products.
By 1999, examination papers were dual-branded with both the AQA and NEAB names. In 2000, [ 1 ] NEAB and AEB/SEG (but not City & Guilds) formally merged under the name AQA. [ 1 ] As NEAB and AEB/SEG overlapped in the qualifications they offered, AQA retained two specifications for many subjects and do until this day, with schools able to choose ...
Colors of a single chemical in different solvents, under visible and UV light, showing how the chemical interacts dynamically with its solvent environmentIn addition to the generic definition offered above, there are several niche fields where the term "chemical substance" may take alternate usages that are widely accepted, some of which are outlined in the sections below.
A specification often refers to a set of documented requirements to be satisfied by a material, design, product, or service. [1] A specification is often a type of technical standard. There are different types of technical or engineering specifications (specs), and the term is used differently in different technical contexts.
Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...