Chemistry Unit 2 Keywords

Once again, here are the Chemistry Unit 2 GCSE AQA Key words and their descriptions I have come across again!

HideShow resource information
Preview of Chemistry Unit 2 Keywords

First 402 words of the document:

C2 Keywords.
Acid: A sour substance which can attack metal, clothing or skin. The chemical is the
opposite of an alkali. When dissolved in water is has a pH less than 7. Acids are
proton (H+ ion) donors.
Activation Energy: The minimum energy needed to start off a reaction.
Alkali: Its solution has a pH of over 7.
Anhydrous: Describes a substance which does not contain water.
Aqueous Solution (aq): The mixture made by adding a soluble substance to water.
Base: The oxide, hydroxide or carbonate of a metal that will react with an acid,
forming a salt as one of the products. (If a base dissolves in water it is called an
alkali). Bases are proton (H+ ion) acceptors.
Brine: A solution of sodium chloride in water.
Catalyst: A substance that speeds up a chemical reaction without being used up or
changed itself chemically by the end of the reaction.
Chromatography: The process whereby small amounts of dissolved substances are
separated by running a solvent along a material such as absorbent paper.
Collision Theory: An explanation of chemical reaction in term of reacting particles
colliding with sufficient energy for a reaction to take place.
Covalent Bond(ing): The attraction between two atoms that share one or more pairs
of electrons.
Delocalised Electron: Bonding electron that is no longer associated with any one
particular atom.
Directly Proportional: A relationship that
when drawn on a line graph, shows a positive
linear relationship that crosses through the
origin.
Electrolysis: The breakdown of a substance
containing ions by electricity.
Electrolyte: A liquid, containing freemoving
ions, which are broken down by electricity in
the process of electrolysis.
Electron: A negatively charged subatomic
particle.
Electroplating: The process of depositing a thin layer of metal on an object during
electrolysis.
Empirical Formula: The simplest ratio of element in a compound.
Endothermic: A reaction that takes in energy from the surroundings, and so cools
down.
Exothermic: A reaction that gives out energy to its surrounding, and so warms up.
Gas Chromatography: The process of separating the components in a mixture by
passing the vapours through a column and detecting them as they leave the column at
different times.

Other pages in this set

Page 2

Preview of page 2

Here's a taster:

Giant Covalent Structure: A huge 3D network of covalently bonded atoms (e.g.
diamond or graphite).
Giant Lattice: A huge 3D network of atoms or ions.
Half Equation: An equation that describes reduction or oxidation, such as reactions
that take place at the electrodes during electrolysis.
Hydrated: Describes a substance that contains water in its crystals.
Intermolecular Forces: The attraction between the
individual molecules in a covalently bonded substance.
Ion: A charged particle produced by the gain or loss of
electrons.…read more

Page 3

Preview of page 3

Here's a taster:

Relative Formula Mass: The total of the relative atomic masses, added up in the
ratio shown in a chemical formula of a substance.
Retention Time: The time it takes a component in a mixture to pass through the
column during gas chromatography.
Salt: A salt is a compound formed when some or all of the hydrogen in an acid is
replaced by a metal (or by an ammonium ion).
Shape Memory Alloy: Mixture of metals which responds to changes in temperature.…read more

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all resources »