General Science - Chemistry

            Mercury

• Nature: Mercury is a chemical element with the symbol Hg and atomic number 80. It is a heavy, silvery-white liquid metal at room temperature. It is unique among metals as it remains liquid under standard conditions.
• Properties: Mercury is known for its high density, low melting point, and high surface tension. It is a poor conductor of heat but a good conductor of electricity. Mercury forms amalgams with many metals, including gold and silver.
• Occurrence: Mercury is found in nature primarily in the form of cinnabar (mercury sulfide, HgS), which is its main ore. It is also found in trace amounts in rocks, soil, and water. Mercury is released into the environment through volcanic eruptions, weathering of mercury-containing rocks, and industrial processes.
• Production: Mercury is extracted from cinnabar ore through a process of heating in the presence of air to produce mercury vapor, which is then condensed into liquid mercury. Significant historical production was in regions such as Spain and Italy, but today, major producers include countries like China and Kyrgyzstan.
• Discovery: Mercury has been known since ancient times. It was used by ancient civilizations, including the Egyptians, Greeks, and Romans. Its liquid form and unique properties were noted by these cultures long before it was understood scientifically.
• Applications: Historically, mercury was used in thermometers, barometers, and various industrial processes. It has been used in the production of chlorine and caustic soda, in the extraction of gold, and in dental amalgams.
• Uses: Mercury is used in a variety of industrial applications, including in fluorescent lamps, batteries, and some types of electrical switches. It is also used in some medical and scientific instruments.
• Health and Environmental Impact: Mercury is highly toxic, particularly in its organic forms (e.g., methylmercury). Exposure can lead to serious health issues, including neurological damage. It is also a significant environmental pollutant, affecting ecosystems and wildlife.

 

 What is the chemical symbol for mercury?

• Answer: Hg

 What is the atomic number of mercury?

• Answer: 80

 At room temperature, mercury is in which state of matter?

• Answer: Liquid

 Which ore is the primary source of mercury?

• Answer: Cinnabar (mercury sulfide, HgS)

 What is the primary historical use of mercury in scientific instruments?

• Answer: Thermometers

Which process is used to extract mercury from its ore?

• a. Electrolysis
• b. Distillation
• c. Chemical precipitation
• d. Roasting
• Answer: d. Roasting

Which of the following is a common application of mercury in industry?

• a. Production of sulfuric acid
• b. Manufacture of chlorine and caustic soda
• c. Production of aluminum
• d. Extraction of iron
• Answer: b. Manufacture of chlorine and caustic soda

What environmental concern is associated with mercury?

• a. Global warming
• b. Ozone layer depletion
• c. Heavy metal pollution
• d. Acid rain
• Answer: c. Heavy metal pollution

Which form of mercury is most commonly associated with health risks from consumption of contaminated fish?

• a. Elemental mercury
• b. Mercury chloride
• c. Methylmercury
• d. Mercury oxide
• Answer: c. Methylmercury