OCR GCSE Chemistry B key terms

Indicator paper coloured with litmus that changes from blue to red under acidic conditions.

The transfer of energy to a liquid that allows gas to form throughout the liquid at its boiling point.

The temperature at which a liquid boils under specified conditions.

The energy required to break one mole of a particular covalent bond in gaseous molecules; bond energy values are usually given in kJ/mol.

A line in a displayed formula representing a covalent bond between two atoms.

The tendency of a material to break rather than bend when a force is applied.

Material present as large pieces or quantities containing very many particles, rather than as individual nanoparticles.

A property of a material made from many particles, such as its melting point, hardness or conductivity.

A product formed alongside the desired product of a process; it may be useful rather than discarded.

An evidence-based statistical estimate of the chance of a specified harmful outcome in a defined population over a stated period.

Checking or adjusting a measuring instrument against a known standard so that its readings are accurate.

A compound containing the carbonate ion, CO₃²⁻.

The removal of carbon dioxide from emissions or the atmosphere, followed by storage so that it does not enter or remain in the air.

A carbon–carbon bond containing two shared pairs of electrons, written C=C; it is the functional group of an alkene.

A toxic gas with the formula CO, formed when carbon-containing fuels undergo incomplete combustion.

A long, narrow, hollow cylindrical fullerene made of bonded carbon atoms.

A place or system, such as a forest or peat bog, that takes in and stores carbon.

A framework of carbon atoms joined by covalent bonds, which may form a chain, branches or a ring.

An organic compound containing the $–COOH$ functional group.

A substance that increases the rate of a chemical reaction and is chemically unchanged at the end of the reaction.

A device in a vehicle exhaust system that uses catalysts to convert carbon monoxide, nitrogen oxides and unburned hydrocarbons into less harmful substances.

The negative electrode in an electrolysis cell, towards which positive ions move.

A positively charged ion, formed when an atom or group of atoms loses electrons.

A relationship in which a change in one factor produces a change in another.

A relationship in which a change in one factor produces a change in an outcome.

To determine the identity, composition, purity or properties of a substance using suitable observations or measurements.

A chemical reaction shown by compounds because they contain the same functional group.