AQA Chemistry A-level Inorganic + Physical Chemistry II Flashcards

Vocabulary flashcards based on definitions and concepts for AQA Chemistry A-level Inorganic Chemistry II, covering properties of Period 3 elements, oxides, transition metals, reactions of ions in aqueous solution, and related definitions.

Acidic solution

A solution with a pH in the range 0-6. Simple covalent oxides of phosphorus and sulfur form acidic solutions when they dissolve in water.

Alkaline solution

A solution with a pH in the range 8-14. Ionic oxides of sodium and magnesium form alkaline solutions when they dissolve in water.

Amphoteric

A substance that is able to react as a base and as an acid.

Oxides

A compound containing oxygen bonded with one other element.

Dissociate

Split up into ions.

Adsorption

The process of forming weak bonds by reactants to a surface of a solid catalyst.

Autocatalysis

A reaction where the product of a reaction acts as a catalyst for the reaction.

Bidentate ligand

Ligands that can only form two coordinate bonds.

Calibration curve

A curve used in colorimetry to plot the amount of absorbance vs concentrations of standard solutions, used to measure the concentration of an unknown solution of a transition metal ion.

Catalyst poisoning

Impurities in a reaction mixture that may bind to a heterogeneous catalyst’s surface and block reactants from being adsorbed.

Cis-trans isomerism

A type of stereoisomerism. Octahedral complexes with four monodentate ligands of one type and two monodentate ligands of another type can show cis-trans isomerism.

Cisplatin

A transition metal compound which is used as an anti-cancer drug. It has a square planar shape.

Colorimeter

Instrument used in spectroscopy which calculates how much light is absorbed by the sample.

Colours in transition metal complexes

Colour arises when some of the wavelengths of visible light are absorbed and the remaining wavelengths of light are transmitted or reflected. The d electrons move from the ground state to an excited state when light is absorbed.

Complex

A central metal atom or ion surrounded by coordinately bonded ligands.

Contact Process

An industrial process used to produce sulfuric acid. Vanadium(V) oxide acts as a heterogeneous catalyst.

Coordinate bond

A covalent bond in which both electrons in the shared pair come from the same atom.

Coordination number

The number of coordinate bonds that are formed with the central metal ion.

d-block

The block of elements in the middle of the periodic table where most elements are transition metals and have their outer electron in the d orbital.

Heterogeneous catalysts

A catalyst that is in a different phase from the reactants. The reaction takes place on the active sites on the surface of the heterogeneous catalyst.

Homogeneous catalysts

Catalysts that are in the same phase as the reactants. They work by combining with the reactants to form an intermediate species which then reacts to form the products and re-form the catalyst.

Ligand

An atom, ion or molecule that forms a co-ordinate bond with a central transition metal ion by donating a pair of electrons.

Ligand substitution

A reaction in which a ligand is substituted by another ligand.

Monodentate ligand

Ligands that can only form one co-ordinate bond.

Multidentate ligand

Ligands that can form more than one co-ordinate bond.

Optical isomerism

A type of stereoisomerism which occurs when a substance exists in two forms that are non-superimposable mirror images. Complex ions can show this when a central metal ion is coordinately bonded to three bidentate ligands.

Redox titrations

A titration experiment to determine the concentration of an unknown solution by carrying out a redox reaction between the two reactants.

Spectroscopy

A technique used to determine the concentration of a solution by measuring how much light it absorbs.

Transition metal

A metal that can form one or more stable ions with a partially filled d sub-level.

Variable oxidation states

The ability of transition elements to form ions with different oxidation states.

Amphoteric

A substance able to react as a base and as an acid. Some metal hydroxides show this character by dissolving in both acids and bases.

Metal aqua ions

Metal ions in aqueous solution. In aqueous solution, the following metal-aqua ions are formed: [M(H2O)6]^{2+}, limited to M = Fe and Cu [M(H2O)6]^{3+}, limited to M = Al and Fe