Thermodynamic Temperature
Thermodynamic Temperature
Different materials can give slightly different thermometer readings. The thermodynamic scale is defined without choosing the property of one material.
A scale that is independent of a substance
This universal scale is the .
Definition
1 markWhat is meant by thermodynamic temperature scale?
Model answer: A temperature scale that does not depend on the physical property of any particular substance.
Key idea
Convert between kelvin and degrees Celsius
Symbols
- = thermodynamic temperature (K)
- = Celsius temperature (°C)
Worked example
Convert a temperature
Convert −37 °C to thermodynamic temperature.
- Add 273.15 to the Celsius value.
- Round only at the end, to match the precision of the given value.
Convert 310 K to degrees Celsius.
Show worked answer
To the nearest degree: 37 °C.
Common mistake
Absolute zero is the lower end of the scale
The lower end of the thermodynamic scale is called .
Definition
2 marksWhat is meant by absolute zero?
Model answer: Absolute zero is the lowest possible temperature. It is 0 K, which is equal to −273.15 °C.
- A kelvin temperature cannot be negative (9702/41/O/N/25 Q4(a)).
- Absolute zero is not a freezing point. It is the lowest possible temperature.
Later, the Ideal Gases chapter uses thermodynamic temperature in gas equations. Complete this scale lesson before using those equations.