OCR GCSE Chemistry B key terms

The change of state from gas to liquid.

A reaction in which monomers join to form a polymer while a small molecule, often water, is formed.

A cooling tube in which vapour changes back into a liquid.

A change from gas to liquid in which energy is transferred from the substance to the surroundings.

The ability of a material to transfer electrical charge or thermal energy.

The degree of trust placed in a prediction or hypothesis in the light of the available evidence.

A third variable that may influence both variables being compared, creating or altering an apparent correlation.

The pattern showing which atoms are directly joined to which other atoms.

The requirement that the total electrical charge is equal on both sides of an ionic or half equation.

The rule that atoms are not created or destroyed in a chemical reaction, so each element must have the same number of atoms on both sides of an equation.

The presence of an unwanted substance in a sample or on equipment, which may affect a test result.

The circumstances surrounding an issue that affect which choice is appropriate.

Production in which materials are fed into a process and product is removed on an ongoing basis.

A comparison experiment used to show what happens when the variable being investigated is absent.

An experiment carried out without the factor being tested, providing a result for comparison.

Adding and combining reagents in a way that controls their amounts and the conditions in which they react.

An action or feature used to reduce the likelihood or severity of harm.

A factor that is kept the same so that different reactions or trials can be compared fairly.

A fraction made from two equivalent measurements, such as $\frac{1000\text{ g}}{1\text{ kg}}$. Its value is one, so multiplying by it changes the unit but not the physical quantity.

A stated equality between two measurements of the same quantity, such as $1\text{ kg}=1000\text{ g}$, used to change the unit without changing the quantity.

A relationship in which two variables show a pattern of changing together.

The gradual destruction of a metal through chemical reactions with substances in its surroundings, commonly involving oxidation by oxygen.

The ability of a material to resist chemical attack by its surroundings.

A strong bond formed when atoms share a pair of electrons.

A compound formed when non-metal atoms share pairs of electrons.

A substance made of atoms joined by bonds in which they share electrons.

A chemical process that breaks long-chain hydrocarbon molecules into smaller, more useful molecules.