What is Barium Definition Properties Compounds and Uses
What is Barium?
Barium is a soft, silvery alkaline earth metal which is highly reactive in nature, due to its high reactivity it is never found in nature as a free element. Barium has atomic number 56 and is represented by the symbol Ba. Barium is the fifth element in Group 2 of the periodic table. The most common compounds of Barium are Barite and Witherite. Barium is never found in the free state but combines with sulfur, carbon, or oxygen.
Properties of Barium
Let us discuss the physical and chemical properties of Barium.
Physical Properties of Barium
Barium is a soft, silvery-white metal with a pale yellow shade and has Ba as its symbol. It has a medium specific-weight and is a very good conductor of electricity. It is difficult to purify Barium so, most of its properties are yet to be determined.
When Barium is kept at room temperature, it forms a cubic structure, It is a very soft metal and expands rapidly on heating. Barium element has a melting point of 1000 K or 730 °C or 1,340 °F whereas the boiling point of Barium is 2170 K or 1900 °C or 3450 °F.
Chemical Properties of Barium
The following table depicts the chemical properties of Barium.
History and Discovery of Barium
During the early middle ages, scientists knew about a few Barium minerals and were attracted to them as Barium minerals would glow for years on exposure to light. As the stones of Barium minerals were found near Bologna, Italy, they were named as “Bologna stones.” Later in the year 1774, a scientist named Carl Wilhelm Scheele discovered that Barium minerals contain an element, but he was not able to isolate Barium.
Occurrence of Barium
Barium never occurs in the free state on earth, and it is always found in a combined form with sulfur, carbon or oxygen. Barium is found 0.0425% on earth’s crust, and 13 μg/L in seawater. The only commercial source for obtaining Barium is Baryte which is Barium sulphate. Other sources for obtaining barium is witherite which is Barium carbonate.
Production of Barium
Barium is produced in various parts of the world such as China, India, Morocco, US, Turkey etc. In the year, 2011, China was the leading producer of Barium. Barium is produced using various methods and processes.
The barium ore is mined, washed, crushed and is separated from quartz then it is reduced to barium sulfide using carbon. The water-soluble barium sulfide is used to make various compounds of barium such as Barium sulphate, barium nitrate or barium carbonate. These compounds can be used to obtain oxides of barium. These oxides are then heated with aluminium at 1,100ᐤC to form BaAl4. This BaAl4 then reacts with BaO to form Barium metal.
Uses of Barium
Barium is a soft metal which has a wide usage in many fields, the following are some general application and uses of barium.
Barium is often used in the form of alloys such as barium-nickel alloy or barium-aluminium alloy in order to reduce unwanted gases from vacuum tubes. It is also used as a drying agent.
Barium is used in fluorescent lamps as impure barium sulfide glows when exposed to light.
Barium is extensively used by oil and gas industries to make drilling mud which makes it easy to drill through rocks by lubricating the drill.
Barium compounds are used to make various house building and decorating materials such as paints, glass, tiles, bricks and rubber etc.
Barium Nitrate is used in fireworks because it provides the fireworks with a green colour.
Barium oxide is used for coating hot cathode such as in cathode ray tubes that facilitate the release of electrons.
Barium peroxide is used in welding works.
Barium as in barium fluoride is used in optic glasses because of its wide transparency range.
FAQs on Barium Chemical Element Overview and Key Concepts
1. What is barium in chemistry?
Barium is a chemical element with the symbol Ba and atomic number 56, classified as an alkaline earth metal in Group 2 of the periodic table. It is a soft, silvery-white metal that is highly reactive, especially with water and oxygen. Barium commonly forms Ba2+ ions in compounds and is never found free in nature due to its high reactivity. It is mainly obtained from minerals like barite (BaSO4) and witherite (BaCO3).
2. What is the electron configuration of barium?
The electron configuration of barium (Ba) is [Xe] 6s2. This means:
- Barium has 56 electrons in total.
- Its configuration is based on the noble gas core xenon (Xe).
- The two outermost electrons are in the 6s orbital, which explains why barium forms Ba2+ ions by losing these two electrons.
3. What is the valency and common oxidation state of barium?
The valency and most common oxidation state of barium is +2. Barium loses its two 6s valence electrons to form the stable ion Ba2+. As a result:
- It forms ionic compounds such as BaCl2 and BaO.
- It shows a fixed oxidation state of +2 in almost all its compounds.
- It does not commonly show variable oxidation states like transition metals.
4. How does barium react with water?
Barium reacts vigorously with water to form barium hydroxide and hydrogen gas. The balanced chemical equation is: Ba(s) + 2H2O(l) → Ba(OH)2(aq) + H2(g)
- The reaction is exothermic.
- Ba(OH)2 is a strong base and dissociates in water.
- Hydrogen gas bubbles are produced during the reaction.
5. What are the main uses of barium in chemistry and industry?
Barium is mainly used in the form of its compounds, especially barium sulfate (BaSO4), in medicine and industry. Key uses include:
- BaSO4 as a contrast agent in X-ray imaging of the digestive system.
- Barium compounds in green fireworks due to characteristic flame color.
- Barium carbonate (BaCO3) in ceramics and glass manufacturing.
- Barium nitrate (Ba(NO3)2) in pyrotechnics.
6. Why is barium sulfate insoluble in water?
Barium sulfate (BaSO4) is insoluble in water because its lattice energy is greater than the hydration energy of its ions. In other words:
- The strong electrostatic attraction between Ba2+ and SO42- ions holds the crystal lattice tightly.
- Water molecules cannot provide enough energy to separate the ions effectively.
- Its solubility product (Ksp) is very low.
7. What color does barium produce in a flame test?
Barium produces a characteristic apple green color in a flame test. This occurs because:
- Electrons in barium atoms are excited by heat.
- When they return to lower energy levels, they emit light in the green region of the spectrum.
- This property is used to identify Ba2+ ions in qualitative analysis.
8. How is barium sulfate prepared in the laboratory?
Barium sulfate is prepared by a precipitation reaction between a soluble barium salt and a soluble sulfate salt. The balanced equation is: BaCl2(aq) + Na2SO4(aq) → BaSO4(s) + 2NaCl(aq)
- BaSO4 forms as a white precipitate.
- This reaction is used as a test for sulfate ions.
- The solid can be filtered, washed, and dried.
9. Is barium toxic to humans?
Soluble barium compounds are toxic, but barium sulfate (BaSO4) is non-toxic due to its insolubility. Key points include:
- Soluble salts like BaCl2 can interfere with muscle and nerve function.
- Toxicity is mainly due to free Ba2+ ions in solution.
- Insoluble BaSO4 passes through the digestive system without being absorbed.
10. How does barium react with oxygen?
Barium reacts with oxygen to form barium oxide (BaO) when heated in air. The balanced equation is: 2Ba(s) + O2(g) → 2BaO(s)
- Barium oxide is a basic oxide.
- It reacts with water to form Ba(OH)2.
- The reaction demonstrates the increasing reactivity of Group 2 metals down the group.
