2006-08-01 22:09:25 · 12 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Mercury is one of only two elements (bromium - Br is the other, from what I remember) that remains as a liquid at room temperature and has a low freezing point, and since it is a liquid, it takes the shape of its container and expands or contracts, depending on the temperature of its' surroundings.
Water wouldn't work because it freezes at 32 degrees F/0 degrees C. Other elements wouldn't work because they are either solids or gases at room temperature, not to mention the fact that their freezing and boiling points are either too high or too low to work with thermometers. This is why we use digital thermometers for temperature extremes.
2006-08-01 22:22:14 · answer #1 · answered by Lizzard 4 · 0⤊ 0⤋
The mercury is the most convenient because
1.Being a metal, it easily gets affected by heat and expands or contracts very fast.
2.It is silvery so is easily noticeable.
3.It does not stick to the walls of the glass thermometer.
4. It is easier to obtain.
5. It is in liquid form at room conditions.
2006-08-02 05:30:14 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Hg is a liquid with a very high melting pt. and boiling pt.,but the real deal is that it is the only liquid metal,metals are used as they have a uniform coeffecient of thermal expansion,so we can notice the changes easily also it is a non wetting liquid and does not get stick to the walls of thermometer
2006-08-02 05:17:46 · answer #3 · answered by sagar 2 · 0⤊ 0⤋
because it is a liquid, so it can move. It also is heavier than most liquids, since it is a metal, so only a small amount of mercury is required for thermometers.
Substances like water expand or compress much more easily than mercury, so if a thermometer were to use that, it would have to be much bigger..... about 32 feet!
This same exact concept applies to barometers, since air pressure and temperature affect substances similarly in respect to volume.
2006-08-02 05:15:02 · answer #4 · answered by Steven B 6 · 0⤊ 0⤋
Mercury is used in thermometers because its coefficient of expansion is nearly constant—that is, the change in volume for each degree of rise or fall in temperature is the same.
2006-08-02 05:19:46 · answer #5 · answered by TK 4 · 0⤊ 0⤋
Mercury is easily affected by even a small change in temp. The increase in volume of mercury with change in temp can be easily measured and is consistent. Mercury is quite stable
2006-08-02 05:15:55 · answer #6 · answered by RAMA K 2 · 0⤊ 0⤋
mercury has a constant co efficient of heating, and thus it is used .
it is also used because it does not stick to the walls of the glass tube it is kept in. it has a high specific heat capacity also due to which it reatcs ti the heat changes very quickly.
2006-08-02 07:35:14 · answer #7 · answered by shaleen c 2 · 0⤊ 0⤋
It is very sensitive to change in temperature and expands evenily
2006-08-02 06:26:01 · answer #8 · answered by Sosela 1 · 0⤊ 0⤋
because Hg is more sensible that other metals and also it is very sensetive to heat.!?
2006-08-02 07:01:32 · answer #9 · answered by cute_si_hayme 2 · 0⤊ 0⤋
You can use alcohol as well but it would freeze if the temperatue got very low.
2006-08-02 05:21:52 · answer #10 · answered by helene_thygesen 4 · 0⤊ 0⤋