OCR GCSE Chemistry B key terms

A feature of a model that prevents it from representing or predicting some aspect of the real system accurately.

The reactant that is used up first and therefore limits the amount of product that can form.

A line or curve drawn to represent the overall trend of plotted data.

A state in which particles remain close together but can move past one another.

A treatment used after chromatography to make otherwise invisible, colourless spots visible.

A scale on which equal numerical steps represent multiplication or division by a fixed factor rather than equal additions or subtractions.

A pair of outer-shell electrons that is not shared in a covalent bond.

An ore containing a relatively small percentage of the desired metal or metal compound.

Land at a low height above sea level, making it particularly vulnerable to coastal flooding as sea level rises.

Able to be hammered or pressed into shape without breaking.

The stage in which raw or processed materials are converted into a finished product.

The total number of protons and neutrons in the nucleus of a particular atom or isotope.

A model that uses quantities and mathematical relationships to describe a system, solve problems or predict behaviour.

The change in the measured quantity divided by the time taken over a stated period.

The process of obtaining a value for a quantity by comparing it with an agreed scale or standard.

The interval within which the true value is reasonably expected to lie, arising from limitations in the measuring equipment and its use.

The transfer of energy to a substance that changes it from a solid to a liquid.

The temperature, or narrow temperature range, at which a solid changes into a liquid.

A separation technique using a membrane with very small pores that allows water to pass while retaining selected particles or dissolved substances.

The curved surface of a liquid in a measuring vessel, used when reading its volume.

An element that typically conducts electricity, is shiny when freshly exposed and forms positive ions in reactions with non-metals.

A compound containing a metal joined to chlorine; Group 1 chlorides have formula $MCl$, where $M$ represents the metal.

An ionic compound containing a metal ion and halide ions, such as potassium bromide.

A compound containing hydroxide ions. A Group 1 metal hydroxide dissolves in water to produce an alkaline solution.

A positively charged particle formed when a metal atom loses one or more electrons.

The electrostatic attraction between positive metal ions and delocalised electrons.

The electrostatic attraction between positive metal ions and delocalised electrons throughout a metal.