What is the temperature range of a mercury thermometer with a Celsius scale?

The temperature range of a mercury thermometer with a Celsius scale is typically designed to accommodate the freezing and boiling points of mercury, as well as the general range of temperatures used in various applications. Mercury freezes at about -39°C and boils at around 356°C. This range allows the thermometer to be effective in measuring ambient temperatures and other applications where precise temperature readings are needed.

The option that states a range of -39° to 315° is appropriate because it covers the entire liquid state of mercury, extending slightly below its freezing point and well into its liquid range, before it reaches higher temperatures. The upper limit of 315°C still provides a reasonable margin below the boiling point of mercury, ensuring that the thermometer can function accurately without reaching its maximum limit.

Other ranges mentioned do not encapsulate the natural state of mercury and its suitability for various temperature readings, particularly the range that includes its freezing and boiling points.