Which statement correctly describes the function and nature of the fixed points used to calibrate a temperature scale on a liquid-in-glass thermometer?
The highest and lowest temperatures that the thermometric liquid is physically capable of measuring.
Two specific physical marks on the glass stem indicating the maximum and minimum expansion limits of the bulb.
Standard, reproducible temperatures based on specific physical states of a pure substance under standard atmospheric pressure.
The points on the scale that represent the thermal equilibrium of the thermometer with its surroundings.
528 exam-style questions on CIE IGCSE Physics 2.2 Thermal properties and temperature, covering 2.2.1 Thermal expansion of solids, liquids and gases, 2.2.2a Internal energy and temperature, 2.2.2b Specific heat capacity, 2.2.3a Melting, boiling, condensation and solidification, 2.2.3b Evaporation, and 2.2.3c Cooling by evaporation. Each one has a worked solution and a mark scheme showing where the marks go.