Key terms & definitions

How closely a recorded value agrees with the true value of the quantity being measured.

How closely a manufactured feature matches its intended dimension, position or shape.

How close a measurement is to the intended or correct quantity.

Reporting information correctly, checking evidence and distinguishing established facts from allegations or opinions.

The size of the place value to which a number has been rounded or truncated, such as $1$, $0.1$ or $100$.

The Persian royal dynasty associated with Cyrus and his successors. Darius used inscriptions at Pasargadae to present himself and Cyrus as members of the same ruling line.

The river-god who competes with Hercules for marriage to Deianira and recounts his defeat in Ovid’s Metamorphoses.

A target that is challenging but possible to reach.

A target that is challenging but realistically possible for the performer’s age, ability and current standard.

A social position gained through a person's own efforts or accomplishments.

Success in education, commonly measured through examination results and qualifications.

A lingering dull pain or soreness, such as discomfort in muscles after exercise.

A particle that donates a proton in a proton-transfer reaction.

A substance that produces hydrogen ions, $H^+$, in aqueous solution.

A dye that changes colour over a particular pH range and is used to show when the titration has reached its end point.

Describes a solution with a pH below 7.

A solution in which an acid produces hydrogen ions, $H^+(aq)$; it has a pH below 7.

A solution with a pH below 7.

The extent to which an aqueous solution is acidic, represented by its pH.

Precipitation made more acidic by pollutants such as sulphur dioxide and nitrogen oxides reacting with water in the atmosphere.

Rain made more acidic than normal when acidic gases such as sulfur dioxide, released by burning coal and oil, dissolve in it. It can damage leaves, acidify lakes and erode buildings.

Rain made more acidic when pollutant gases, including sulfur dioxide and oxides of nitrogen, form acids in atmospheric water.

Rain made more acidic by pollutants in the atmosphere, including sulfur dioxide from burning sulfur-containing fuels.

Rain made more acidic by air pollution, including sulphur dioxide released during fuel combustion.

Rain made more acidic by atmospheric pollutants, including sulphur dioxide, which can damage trees and aquatic environments.

Water with an acid, such as lemon juice, added to help control browning in prepared fruit or vegetables.

Coding information in terms of how it sounds.

Acceptance of something without actively resisting it; this does not necessarily mean enthusiastic agreement.

A characteristic developed because of environmental conditions rather than inherited genetic information.

A characteristic that develops during an organism’s lifetime because of environmental influences, rather than being inherited through its alleles.