Question

1. explain why mercury is rarely used in modern thermometers.

Explanation:

Mercury is toxic. If a mercury - thermometer breaks, mercury vapor (which is harmful when inhaled) can be released. Also, mercury has a relatively high freezing point (\(-38.83^{\circ}C\)) compared to some other liquids used in thermometers (like alcohol which freezes at \(-114.1^{\circ}C\)), so it cannot be used to measure very low temperatures accurately.

Answer:

Mercury is toxic (releases harmful vapor if thermometer breaks) and has a relatively high freezing point (cannot measure very low temperatures well), so it is rarely used in modern thermometers.