Who discovered chlorine?

Chlorine is denoted by Cl and its atomic number is 17. Sodium chloride or salt is a very common compound of chlorine, which has been in use since ancient times. Evidence suggests that rock salt has been used as early as 3000 BC. In 900 AD, a Persian alchemist named Rhazes prepared hydrochloric acid, another compound of chlorine. In 1200 AD, a mixture of hydrochloric acid and nitric acid was used to dissolve gold. This process released chlorine gas, but it was not known at that time.

The first person to isolate chlorine gas was Carl Wilhelm Scheele, a Swedish chemist in the year 1774. As a result, he is credited for discovering chlorine. But he did not know that it was an element. It was only in 1810 that Sir Humphry Davy realized that Scheele had actually discovered a new element. Scheele, on the other hand, had studied its properties and discovered that it could kill insects, had a green yellow colour and that it bleaches litmus paper. Chlorine has many practical purposes in our life. It is used to purify water, to prepare disinfectants, in bleaches and in mustard gas. It is also used to manufacture many products directly or indirectly. For example, it is used in paper production industry, in making dyes, antiseptics, insecticides, paints, petroleum products, plastics, medicines, textiles, solvents and even some food items. It kills bacteria and microbes in the drinking water supplies. Chlorine is also used to bleach wood pulp for paper-making and to remove ink from recycled paper.

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From where did selenium get its name?

The element with the atomic number 34 is selenium. It was discovered by Jons Jacob Berzelius, a Swedish chemist, in 1817. He discovered selenium while analyzing an impurity in sulphuric acid that was produced at a factory in Sweden. Berzelius thought that this impurity was tellurium at first, but he then realized that it was an unknown element. And because of its similarity to tellurium, he named it selenium after the word Selene - a word in Greek that means ‘moon goddess’.

Selenium began to be used on commercial levels by the mid-1870s when it was developed by Werner Siemens. A selenium cell was used in the photo-phone developed by Alexander Graham Bell in 1879.

This metal is also nutritionally essential for humans. We need selenium for healthy joints, hearts, and eyes. It is critical in DNA synthesis, in the activities of the immune system, and the reproductive system. Selenium also helps fight cancer, among other diseases. The human body cannot synthesize this element, and therefore, we have to provide it from outside sources. However, a little selenium is all that is needed for healthy functioning and too much selenium can be toxic.

Selenium exists in several allotropic forms, of which only three are generally recognized. Amorphous selenium is either red, in powder form, or black, in vitreous or glassy form. Crystalline hexagonal selenium is the most stable form of this metal. It resembles sulphur in its appearance.

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Who discovered germanium?

The existence of germanium was also predicted by Dmitri Mendeleev in 1869 when he developed the periodic table of elements. The atomic number of the element is 32.

In 1885, Clemens Winkler, a German chemist, discovered an element that was referred to as “eka-silicon” in an ore known as argyrodite. This ore contained silver, sulphur, iron oxide, and zinc along with about 7 per cent of this unknown metal.

The word “germanium” is derived from the Latin name for Germany, which is the home country of Winkler, who discovered it.

It was first used commercially during World War II in high-resolution radar receivers. The first germanium transistor was invented after this application. Though there are claims that germanium supplements have health benefits, research has not yet found evidence for those claims.

On the other hand, using germanium supplements or medications might lead to side effects such as kidney damage, anaemia, muscle weakness, lack of body coordination, and increased liver enzymes.

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Who predicted the existence of gallium?

It was Dmitri Mendeleev who first predicted the presence of gallium even before its discovery. Mendeleev named this hypothetical element as eka-aluminium because he had calculated that the element would sit below aluminium in the periodic table.

Gallium’s atomic number is 31. French chemist Paul E. Lecoq de Boisbaudran was the person who discovered it through a spectroscope in 1875 in Paris. De Boisbaudran had extracted gallium from a zincblende ore from the Pyrenees. Initially, he had obtained only 0.65 grams from 430 kilograms of ore. But later, he isolated gallium by the electrolysis of gallium hydroxide in potassium hydroxide solution.

Gallium exists as a soft, silvery metal. It is primarily used in electronic circuits, semiconductors, and light-emitting diodes (LEDs). Gallium is also used in high-temperature thermometers, barometers, pharmaceuticals and nuclear medicine tests. This metal is used in electronics in the form of gallium arsenide (GaAs). In fact, nearly 95 per cent of the gallium produced is used to make GaAs, which is a compound used in microwave, semiconductors, and blue and violet LEDs. Gallium is also used in the pharmaceutical industry, particularly radiopharmaceuticals. The radio-active isotope Ga-67 is an isotope of Gallium, which is used as a nuclear medicine test to check for inflammation, or cancer in the body.

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What is the role of India in the smelting of zinc?

Indians were the first to develop the technology to smelt Zinc in the 12th century. Zinc got its name from the German word ‘zinke’ which means pointed. The term might be related to the sharp, pointed crystals that are formed from smelting zinc.

In 1746, German chemist Andreas Marggraf figured out a way to isolate zinc by heating carbon and calamine (which makes calamine lotion). He reported his finding in great detail, which earned him the credit for discovering zinc. But much before his report, several other European researchers had already discovered zinc. William Champion, an English metallurgist, even had the patent for the process long before.

Zinc is a white powder that is used in everything from sunscreens to solar cells and nuclear reactors. It helps prevent corrosion in many items. Zinc is also an important element in health. It is essential to keep the body’s enzymes functioning well. The deficiency of zinc can slow growth and affect the immune system. Sometimes zinc deficiency can cause abnormalities in smell and taste as the metal is critical to these functions.

Zinc has the atomic number of 30.

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Why is the story of the discovery of nickel interesting?

Nickel, atomic number 28, was not discovered as an element until the 1750s although it has been in use since ancient times. In Saxony of Germany, the miners reported the presence of a dark red ore with a green coating, which caused irritation to them. They believed that this was an ore of copper, but they could not extract any copper from it. They thought that it was the work of some goblins which was preventing them from extracting copper. As a result, they named it ‘kupfernickel’, which is translated as ‘goblin’s copper’.

Between the years 1751 and 1754, Axel Cronstedt, a Swedish chemist conducted many experiments to find out the true nature of kupfernickel. He found out that this new compound did not yield the results a copper compound would yield and that it resulted in a hard white metal upon being heated with charcoal. This made Cronstedt conclude that he had found a new element. As a result, he named the new element nickel based on kupfernickel from which he isolated it.

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Who discovered chromium? What are the major uses of the element?

Chromium has the atomic number 24. It was discovered by a French chemist named Nicolas Louis Vauquelin in Paris in 1780. Vauquelin discovered the element in a mineral sample of ‘Siberian red lead’, which is now called crocoite (lead chromate). He prepared a solution of chromic acid with lead carbonate and potassium salt by boiling the crushed crocoite with potassium carbonate. He further investigated this yellow solution and confirmed that he had found a new metal. In 1781, Vauquelin had succeeded in isolating the metal. He was also successful in identifying small amounts of chromium in ruby and emerald stones.

Chromium has a silvery, shiny appearance, and it is used to coat cars, stoves and other appliances to protect them from corrosion. It has a high melting point and a stable structure, which makes it very useful in the textile and refractory industries. Chromium gets its name from the Greek word chroma, which means ‘colour’. This element when combined with other elements in nature, produces very vibrant colours, which are used as dyes.

In terms of abundance in the Earth’s crust, chromium is twenty-first in order. Chromium is mostly found in chromite ores. This ore is the primary source of chromium and is often used to make bricks because of its high melting point, moderate thermal expansion and stable crystal structure.

Chromium is very detrimental to health. Consuming high levels of chromium through polluted drinking water or inhaling the fumes of heated chromium leads to ulcers, cancer and other health problems.

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What are the uses of manganese?

One of the most important uses of manganese is in the manufacture of glass. This was mentioned in the first century AD by Pliny the Elder, a Roman author, who described how a black powder (which is manganese dioxide) was used to manufacture colourless glass. The existence of manganese as a separate element was first recognised in 1740 when Johann Heinrich Pott, a German chemist, stated that pyrolusite (manganese dioxide) contained a new earth metal. Until this discovery, pyrolusite was believed to be a compound of iron. To prove his point, Pott prepared potassium manganate by fusing caustic potash (potassium hydroxide) with pyrolusite in air.

Ignatius Gottfried Kaim, an Austrian chemist, was the first to isolate manganese in 1770. But his sample was not pure, and several attempts at isolating the pure metal failed. Later, Johan Gottlieb Gahn, a Swedish chemist, almost produced pure manganese in 1774 when he produced a white, hard, brittle metal. But Gahn’s manganese was also impure.

The physical properties of manganese include being very hard and brittle. Manganese is one of the most common elements found in the Earth’s crust. One can find it across the planet’s surface. It is also vital to human and animal life as it supports various metabolic functions.

Alloys of manganese are used in steel production and glass-making.

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When was vanadium discovered?

Vanadium, atomic number 23, was discovered in 1801 by Andres Manuel del Rio, a Spanish scientist. Del Rio named this element as eritrono or erythronium from the Greek word eruthros, which means red. But in 1805, the French chemist Hippolyte-Victor Collet-Descotils, who examined the ore, announced that erythronium was just impure chromium. This analysis was accepted by del Rio as well.

No further study was done on the element until 1830, when Nils Gabriel Sefstrom, a Swedish scientist, found a new metal in an iron ore in Stockholm. He called this new element vanadium after Vanadis, the Scandinavian Goddess of beauty, as the compounds formed by this metal were extremely beautiful.

Later a German chemist named Friedrich Wohler reinvestigated the Mexican lead ore to find that vanadium was similar to del Rio’s erythronium.

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Who discovered titanium?

William Gregor, a Cornish clergyman was the first to discover titanium while studying sand deposits in the Manaccan valley in 1791. In his sample, he identified an oxide of iron and an unknown metal, which he called ‘menachanite’. This being said, Gregor’s contribution to titanium’s discovery was forgotten, although the oxide he identified is titanium’s most important commercial ore. The ore is now known as ilmenite.

Later, the element was rediscovered by Martin Heinrich Klaproth, a renowned German scientist, in 1795. When he discovered titanium, he named the unidentified metal after the Titans of Greek mythology. But Klaproth could not isolate titanium. It was in 1887 that metallic titanium was isolated by Lars Nilson and Otto Pettersson. They achieved a purity of 95 percentage.

Titanium was isolated with 99 percentage purity by Henry Moissan using an electric furnace in 1896. Later, in 1910, Matthew A. Hunter, an American metallurgist, isolated pure titanium.

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What makes scandium expensive?

Scandium is a chemical element that is also a rare metal. It is represented by Sc and its atomic number is 21. In 1871, Dmitry Mendeleev, a Russian chemist, predicted the existence of scandium, but it was discovered only in 1879 by Lars Fredrik Nilson. It occurs in many minerals, but in minute quantities.

Scandium has many unique properties and uses. It is also very expensive due to its scarcity and limited production. Pure scandium costs approximately $7000/ per kg. Although it is rare on Earth, Scandium is present in abundance in our universe.

Although there is a lack of extensive research about the health and safety issues of scandium, it is generally considered non-toxic. But certain compounds of scandium such as scandium chloride can be lethal. As a result, such compounds should be handled with care.

Scandium is mostly found in low concentrations, but it is plentiful throughout the world, In fact, the metal has a crustal abundance that is even higher than that of lead. In total, there are 22 parts per million by weight of scandium in the ground.

But even if there is plenty of scandium being discovered, processing it can be difficult and that is why there are very few stable sources of this metal. As a result, we do not see scandium being used commercially. A lot of research is happening on this metal, so once stable sources are found, scandium might be used for many things.

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Why is calcium an important element?

Calcium is an alkaline earth metal represented by Ca. Its atomic number is 20. It is a reactive metal that reacts with air to form a dark oxide layer on its surface. It shows similar physical and chemical properties as that of strontium and bariunm, which are heavier elements that fall in the same group. They are all homologous in nature.

Calcium is the fifth most abundant element in the Earth’s crust. It is also the third most abundant metal after iron and aluminium. In the human body, calcium is the most abundant metal and the fifth-most abundant element.

Calcium carbonate, which is found in limestone and fossils of early sea life, is the most common calcium compound. Gypsum, anhydrite, fluorite, and apatite are some other sources of calcium. The name calcium is in fact derived from the Latin term ‘calx’ which means lime that was obtained from heating limestone. 

Although our ancestors knew some calcium compounds, they did not know the chemistry of it until the seventeenth century. Pure calcium was isolated in 1808 by Humphry Davy, who named the element. He used the process of electrolysis to isolate the element. The major uses of calcium compounds are in foods and pharmaceuticals industries for calcium supplementation, in the paper industry as bleaches, and as components in cement and electrical insulators. It is also used in the manufacture of soaps. In its pure form, calcium has few applications due to its highly reactive nature. But it is used in small quantities in steel-making to form alloys. It is also used in automotive batteries as calcium-lead alloys.

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Which was the first element discovered using electrolysis?

Potassium was the first element to be discovered using the process of electrolysis. It was discovered by Humphry Davy, a young British man, who was working as an apprentice to a surgeon-apothecary in the year 1807. Davy was fascinated by the science of passing electrical current through various substances to break them apart. This process is what we now call electrolysis. He obtained potassium from potassium hydroxide through this process and a few months after discovering the element, Davy isolated sodium using the process of electrolysis.

Potassium gets its name from the English word potash. Its chemical symbol is K, which comes from kalium, the Medieval Latin word for potash. It is believed that kalium was derived from the Arabic word qali, which means alkali. Potassium has low density for a metal and it appears as a shiny, lustrous metal at room temperature. It reacts vigorously with water to form hydrogen gas. It burns with a bright red colour in a flame test.

Potassium is a vital mineral needed for the body. It helps to regulate fluid balance, muscle contractions, and nerve signals. Including more potassium in your diet can also help to reduce blood pressure and water retention. Such a diet also protects our body against stroke and prevents diseases like osteoporosis and kidney stones.

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When was argon discovered first?

Argon was discovered in 1894. Before that, in 1785, Henry Cavendish had suspected that there was a very interactive gas in our atmosphere but he couldn’t identify it. Later, in 1882, H.F Newall and W.N Hartley looked at the colour spectrum of air and found some strange lines they couldn’t account for. It was in 1894 that Lord Rayleigh and Sir William Ramsay, removed all the oxygen and nitrogen from a sample of air and discovered that it was argon that had caused those strange lines.

Argon is represented by Ar and is a chemical element with atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the most abundant noble gas in our atmosphere. 

Argon is chemically very inactive and its name is derived from “argon” which means ‘lazy one’ in Greek. It is colourless, tasteless, odorless and non-toxic in gaseous and liquid forms. It is unreactive (inert) in almost all forms and conditions. As a result, argon doesn’t form any stable compounds at room temperature.

Argon is slightly soluble in water and it has the same solubility as oxygen gas. It is three times more soluble than nitrogen gas in water. Although argon is mostly unreactive, scientists have determined that it can form argon hydrofluoride (HArF) in specific conditions. Planet Mercury has a very thin atmosphere, which contains up to 70 per cent argon.

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Why was aluminium very costly in earlier times?

Aluminium is the most abundant element found in the crust of the Earth. It was first discovered by Hans Christian Oersted, a Danish physicist and chemist in 1825. And later, it was discovered by Friedrich Wohler, a German chemist in 1827. But Wöhler’s method could not produce aluminium in great quantities and the metal continued to be a rare metal. In fact, it was costlier than gold. As a result, aluminium was regarded highly at that time. There is a popular story that Napoleon, the famous French emperor, used aluminium knives and forks, while others at the table used silver tableware. It is also said that the King of Thailand once used an aluminium bracelet.

Aluminium is mostly used in the production of construction materials and kitchen utensils. In 1886, Paul Héroult, a French engineer, and Charles Martin Hall, an American engineer, independently electrolyzed a mixture of molten bauxite and cryolite to produce aluminium. This laid the foundation for large-scale production of the metal in later years. After this, two aspects of aluminium changed completely: firstly, it could be mass-produced and was no longer considered as a precious metal; secondly, the mass production of aluminium led to its widespread use in making of industrial and domestic products, which gradually replaced the use of other metals like steel and copper.

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