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1. Mercury has low vapor pressure. It is more sensitive to changes in atmospheric pressure than water.
2. The freezing point of mercury is lower than that of water. It can can record the atmospheric pressure at temperatures below that of 0 degrees centigrade.
3. Mercury shines brightly. This ensures that markings on the tube can be read accurately and easily.
4. Mercury does not evaporate easily so very little mercury vapor enters the vacuum above the mercury in the tube.
chrispohmomanyi answered the question on September 20, 2017 at 07:23
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