A-Level Chemistry revision notes

A-Level (A2/AS) Chemistry revision notes providing information and assistance across all examination boards including AQA, CIE, OCR, Edexcel, Eduqas & WJEC. Chemistry is a complicated A-Level with a lot of content and information to work through. We have put together some of the best revision notes and learning materials to hopefully make sitting your Chemistry A-Levels a little bit easier and stress-free.

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The Mole

Definition The mole (n), abbreviated as mol, is a fundamental chemical quantity that characterizes the amount of substance. It is defined that 1 mole of any substance contains 6.02x1023 particles (atoms, molecules, ions, electrons). 6.02x1023 is a unique number, called Avogadro’s number. Amedeo Avogadro was the first scientist to determine the actual number of particles ...

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Summary Thermochemistry is a branch of Thermodynamics, a scientific field that comprises the relationships between heat, work, and other forms of energy resulting from different chemical and physical processes. Thermochemistry itself is defined as energy changes when a chemical reaction takes place.  Energy is the capacity to supply heat or do work. Thermochemistry is concerned ...

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Bond Enthalpy

Summary Bond enthalpy, also referred to as bond energy or bond dissociation energy, is the energy required to break a particular covalent bond in one mole of molecule in a gaseous state. The term was previously used as “bond strength.” These terms have the same exact meaning; therefore, it can be used interchangeably.  Bond Enthalpy ...

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Essential Elements for Life

Summary There are about 118 sorted by atomic number in the Periodic Table. 94 out of these 118 elements are considered as natural elements, and 20 to 25% of them are known as “essential to life.” These essential elements are quite similar among organisms but vary from species to species (e.g., humans need 25 elements ...

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Reaction Of Ions In Aqueous Solutions

Key Information & Summary A solvent is a liquid that dissolves a solid, liquid or gaseous compound called solute, giving rise to a solution. The solvation (or dissolution) in chemistry is interaction between solute and solvent that brings the single dissolved solute molecules to surround themselves with solvent molecules. If the solvent responsible for solvation ...

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Organic analysis

Key Information & Summary The first operation is the determination of the chemical-physical properties: the melting point of the solid compounds, the boiling point of the liquid compounds. The qualitative research of the elements follows, trying to discover if, in addition to carbon and hydrogen, there are other elements such as nitrogen, sulfur, halogens, etc. ...

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Optical isomerism

Key Information & Summary Two compounds with the same brute formula are called isomers. There are different types of isomers: homomers, stereoisomers, constitutional isomers. In particular a stereocenter or stereogenic center is any point in a molecule bearing groups, such that an interchanging of any two groups leads to a stereoisomer. The presence of the ...

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Key Information & Summary Polymers are macromolecules made up of repeating units called monomers. Polymers can be synthesized through two types of polymerization reactions i.e. addition and condensation polymerization. Polymers exist as amorphous or crystalline solids. Polymers can be classified as organic, inorganic, synthetic and mixture of organic-inorganic polymers. Polymers may be classified as heteropolymer ...

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