critical temperature
critical temperature — noun
1. the temperature above which no amount of pressure will squeeze a gas back into l
the temperature above which no amount of pressure will squeeze a gas back into liquid form.
Carbon dioxide has a critical temperature of about thirty-one degrees Celsius.
the critical temperature of [substance]
Above its critical temperature, the gas refused to turn into a liquid under any pressure.
above its critical temperature, [no liquid forms]
Sofia cooled the steam until it dropped below the critical temperature and became water.
cooling below the critical temperature to form a liquid
Engineers keep the tank below the critical temperature to store the fuel as a liquid.
The students measured the critical temperature of water at just over three hundred degrees.
- above the critical temperature
- below the critical temperature
- reach the critical temperature
- critical point
the full pressure-temperature point; critical temperature is just its temperature part
Grammar Patterns
the critical temperature of [substance]
Usage Note
Subject is usually a named substance (water, oxygen, carbon dioxide). Distinguish from sense 2, which is about a solid changing its internal structure rather than a gas failing to liquefy.
Common Mistakes
2. the temperature at which a solid switches from one internal arrangement of its a
the temperature at which a solid switches from one internal arrangement of its atoms to another, such as when iron stops being magnetic.
Iron loses its magnetism once it is heated past its critical temperature.
heating a solid past its critical temperature
At the critical temperature, the metal's atoms rearrange into a new crystal pattern.
atoms rearrange at the critical temperature
Kwame recorded the exact critical temperature at which the steel sample changed its structure.
Below the critical temperature, the alloy keeps its original hard and brittle form.
- past the critical temperature
- the critical temperature of the metal
- transition temperature
broader term for any point where a material's phase or form changes
- Curie point
the specific critical temperature where a metal loses its magnetism
Grammar Patterns
the critical temperature for [transition]
Usage Note
Only sense that describes a solid reorganising its atoms; the magnetic version is also called the Curie point. Distinguish from sense 1, where a gas fails to become a liquid.
Etymology
A compound term built from 'critical', meaning a turning point or decisive limit, and 'temperature'. The phrase entered scientific English in the nineteenth century as physicists studied how gases turn into liquids and how solids change their internal form at fixed heat thresholds.