Question

Why mercury is preferred in thermometers?

Answer 1

Mercury is preferred in thermometers due to the following reasons:-

1. Mercury doesn't freeze or vaporise easily i.e. it remains liquid over a large temperature range.
2. Since mercury is a good conductor of heat, it quickly attains the temperature of the body with which it is in contact.
3. Mercury doesn't wet the surfaces in contact thus it doesn't stick to the inner surface of the capillary tube.
4. Mercury is an opaque liquid with a shining appearance like silver. Thus it can be easily seen through the glass.