Question

you are planning to go to a very cold place where the night temperature drops
to -50 C. Which thermometer will you take with you - mercury or alcohol? Why?

Answer 1

If an alcohol thermometer utilizes a combination of ethyl alcohol, toluene, and pentane, its lower temperature range may be extended to measure temperatures down to as low as −200 °C (-328 °F). However, the measurement temperature range c. −200 °C to 78 °C, is highly dependent upon the type of alcohol used.
Because of this it's capacity to measure such low temperatures alcohol thermometer is used