Aarushhh/wikipedia-simple-splitted huggingface dataset:
Hooke's collaboration with Christopher Wren included St Paul's Cathedral, whose dome uses a method of construction conceived by Hooke. Hooke also participated in the design of the Pepys Library, which held the manuscripts of Samuel Pepys's diaries, the most frequently cited eyewitness account of the Great Fire of London.

In the reconstruction after the Great Fire, Hooke proposed redesigning London's streets on a grid pattern with wide boulevards. This pattern was used in the later renovation of Paris, Liverpool, and many American cities. The proposal was rejected. The opponents 
argued that in practice property owners were secretly shifting their boundaries. Hooke was in demand to settle many of these disputes, due to his skill as a surveyor and his tact as an arbitrator.

Related pages
 Physicist
 List of physicists

References 

1635 births
1703 deaths
English biologists
English naturalists
Fellows of the Royal Society
English science writers
English architects
Polymaths
Emission is a word that originally comes from Latin. Originally it means something that is sent out. Several things can be sent out:

 The most common use talks about emission of toxic gases. Those gases get produced by factories and motors, like motors in cars.
 People talk about radio emissions. Those are programmes that people can listen to if they have a radio receiver.
 There could be emissions of loud noise, someone might be making loud noises.
 There also are emissions of light.
Count Lev Nikolayevich Tolstoy (9 September 1828  20 November 1910) was a Russian novelist and anarchist, famous for writing the books War and Peace and Anna Karenina, and many other works. He was a Christian and believed in non-violence and practiced simple living. His work The Kingdom of God is within you has influenced people like Mahatma Gandhi and Martin Luther King.

Early life
Tolstoy was born at Yasnaya Polyana, the family estate in the region of Tula, Russia and he married Sofia Andreevna Bers.

Death
Tolstoy died in 1910, at the age of 82. He died of pneumonia.

Life and career 
When he was young his parents died, so he and his siblings were brought up by relatives. At the age of 16, he began studying law and oriental languages. Unfortunately, he left University in the middle of his studies and spent much of his time in Moscow and Saint Petersburg. Later on in his life, he joined the Army with his brother after running up some heavy gambling debts. It was at that time that he started writing.
His conversion from a wealthy society author to the non-violent and spiritual anarchist of his later days was notable. It was caused by his experience in the army as well as two trips around Europe in 1857 and 1860–61. Others who followed a similar path were Alexander Herzen, Mikhail Bakunin and Peter Kropotkin. During his 1857 visit, Tolstoy saw a public execution in Paris, an experience which marked the rest of his life.

After Anna Karenina, Tolstoy concentrated on Christian themes, and his later novels such as The Death of Ivan Ilyich (1886) and What Is to Be Done? (1886) develop a radical Christian philosophy which led to his excommunication from the Russian Orthodox Church in 1901. 

After shaping both his political and literary development in Europe, he returned to Russia and founded 13 schools for Russia's peasant children.

Related pages 
List of Russian-language novelists
List of Russian novelists

References
References 

1828 births
1910 deaths
Anarchists
Deaths from pneumonia
Infectious disease deaths in Russia
Russian Christians
Russian novelists
People have made wine in the American state of California for a long time. California has become recognized as making some of the world's best wine. California makes most of the wine that is made in America.

History
People first made wine in California in 1769. Missionaries from Mexico brought their wine plants to produce wine for the mass. Later, people coming from Europe improved the making of wine. They had brought their own kinds of wine plants.

Before 1920, there was more wine made every year. Then Prohibition began. During Prohibition, it was not allowed to sell alcoholic drinks in the United States. It almost ended the making of wine in California. Californian wine-making took a long time to recover.

In 1990, the USA sent less than five percent of its wine to other countries. After that, exports of wine from California increased. Today, the USA is one of the big wine industries.

Wines
Wines 

Wine comes in different colors. Most wines are called "red" or "white". White wine is not really white, it just has a very light color.  54 percent of the Californian wines are white wines. Some examples of white wines are Chardonnay and Sauvignon Blanc. Some examples of red wines are Zinfandel, Cabernet-Sauvignon, Merlot, and Pinot Noir.

Cool climate viticulture 
Grapes for wine used to need warm weather. People wanted to grow more grapes, so they learned how to grow them where the weather was not as warm. That way of growing grapes is called "cool climate viticulture". Vines are now planted in colder places, up to  above sea level. Monterey County was the first place where that was done.

Wine regions 

In California, there are more than 800 wine cellars. Wine cellars are big rooms were wine is stored. They are part of a winery, the place where wine is produced.
Two of the most famous growing areas for wine in California are Napa County and Sonoma County. The wines from those places are some of the best in the world. Some examples of the wines made there are Chardonnay and Cabernet Sauvignon.

Other known wineries are in Mendocino, in the Lake Counties, Santa Maria and Santa Barbara.

References

Other websites 
3000 word report - Comprehensive overview Pinot Noir Wine 

Wine
Wine
Butch Cassidy and the Sundance Kid is a 1969 American movie from 20th Century Fox. George Roy Hill directed it, and John Foreman produced it. It stars Paul Newman and Robert Redford as two robbers in Wyoming who go to Bolivia to escape the law.

The movie was loosely based on the real story of the two title characters (Butch Cassidy and his friend Harry Longabaugh, also called "Sundance"). But it made the legends of the two more popular.

It won four Academy Awards: for Best Cinematography (shooting work on a movie), Best Original Score, Best Song (Burt Bacharach's "Raindrops Keep Fallin' on My Head") and Best Original Screenplay (William Goldman). It was also nominated for Best Picture, Best Director (Hill) and Best Sound. Goldman won the BAFTA Award for Best Screenplay.

It was one of the largest-grossing movies of the 1960s (with $102.3 million in the United States). It was number fifty on AFI's 100 Years... 100 Movies list.
At first, Warren Beatty and Steve McQueen (even Marlon Brando) were called upon to play the title roles. When Newman and Redford took their place, the roles were switched, with Newman as Sundance, and Redford as Cassidy. The studio, 20th Century Fox, did not like Redford's role. But the movie's director, Hill, wanted it that way.

As a result, Redford has said that the movie made him a more famous actor.

The Sundance Film Festival is named after Redford's role, as well his Utah ski resort.

References

Other websites 

 Movie 

1969 movies
1969 crime movies
1960s Western (genre) movies
20th Century Fox movies
BAFTA Award winners
English-language movies
United States National Film Registry movies
American crime movies
American Western (genre) movies
American buddy movies
Movies set in Wyoming
Multilingual movies
Movies that won the Best Original Song Academy Award
Movies directed by George Roy Hill
The 1480s was a decade that began on 1 January 1480 and ended on 31 December 1489.

Events 
 War of the Roses in England.
 Bartolomeu Dias of Portugal sails around Africa and on to India.
 Spanish Inquisition begins.

Births 
 Martin Luther, German monk and reformer 
 Raphael, Italian painter and architect 
 Huldrych Zwingli, Swiss religious reformer 
 Catherine of Aragon, queen of Henry VIII of England

Deaths 
 Mehmed II, Ottoman Sultan 
 King Christian I of Denmark and Norway 
 Axayacatl, Aztec ruler of Tenochtitlan
Mehmed II  (; , ; 30 March 14323 May 1481), commonly known as Mehmed the Conqueror (; ), was an Ottoman sultan who ruled from August 1444 to September 1446, and then later from February 1451 to May 1481. In Mehmed II's first reign, he defeated the crusade led by John Hunyadi after the Hungarian incursions into his country broke the conditions of the Peace of Szeged. When Mehmed II ascended the throne again in 1451, he strengthened the Ottoman navy and made preparations to attack Constantinople. At the age of 21, he conquered Constantinople (modern-day Istanbul) and brought an end to the Byzantine Empire, permanently cementing its destruction.
Mehmed continued his conquests in Anatolia with its reunification and in Southeast Europe as far west as Bosnia. After conquering Constantinople and getting the Byzantines out of the way, he started making more conquests in the Balkans and focused on his Balkan campaigns, even unsuccessfully laying siege to Belgrade in 1456 at one point. He was also known for his rivalry with Vlad the Impaler, who grew up at his father's court alongside him. Vlad the Impaler had taken control over Wallachia and rebelled against the Ottoman Empire, thus Mehmed II sent an Ottoman army, resulting in a war between the two. The war ended when Vlad was killed by an Ottoman patrol in Wallachia. He was then beheaded with some saying his head was sent to Mehmed II himself at the capital city Constantinople (modern Istanbul) by the Ottoman soldiers. He was also known for his campaigns against Albanian rebel leader Skanderbeg. For most of his reign, Mehmed II was on campaign against either John Hunyadi, Vlad the Impaler or Skanderbeg
. Domestically, he made many political and social reforms, encouraged the arts and sciences, and by the end of his reign, his rebuilding program had changed Constantinople into a thriving imperial capital. He is considered a hero in modern-day Turkey and parts of the wider Muslim world. Among other things, Istanbul's Fatih district, Fatih Sultan Mehmet Bridge and Fatih Mosque are named after him.
Related pages
Byzantine Empire
Sultan
Turkey

References

Other websites

Biography page at OttomanOnline 

Sultans of the Ottoman Empire
History of the Middle East
1481 deaths
The Bold and the Beautiful is a popular American soap opera. After The Young and the Restless, it is the highest-rated soap opera there.

The series is shown in over 100 countries. About 300 million people watch it every day. This makes The Bold and the Beautiful the most watched television series in the world. The first episode was shown on March 23, 1987 on the CBS network. The series was created by the soap opera writer William J. Bell and his wife, Lee Phillip Bell. It is the only American soap opera to have its daily episodes translated into Spanish for the Hispanic viewers in the United States.
The series is set in Los Angeles, California. It tells the story of the Forrester family, who owns a fashion empire called Forrester Creations. The major members of the family are Eric Forrester (played by John McCook), the president of Forrester Creations, his wife Stephanie (Susan Flannery), their eldest son Ridge (Ronn Moss) and Brooke Logan (Katherine Kelly Lang), who was married to both the father and the son. She owns most of Forrester Creations. This is because she created BeLieF, a formula which earned much money for the company. There used to be a second fashion company called Spectra Fashions. It was Forrester’s main competitor. The conflicts between the Forrester and the Spectra families was one of the major themes of the story.

List of actors/characters on the show

Other websites 
 
 Official site
 The Bold and The Beautiful
 The Bold and The Beautiful CBS Website
1987 American television series debuts
1980s American drama television series
1990s American drama television series
2000s American drama television series
2010s American drama television series
American soap operas
CBS network shows
Television series set in Los Angeles
English-language television programs
Primary colors (or primary colours in Commonwealth English) are sets of colors that can be combined to make a useful range of colors. The primary colors are those which cannot be created by mixing other colors in a given color space.

For subtractive combination of colors, as in mixing of pigments or dyes for printing, the CMYK set of primaries is often used. In this system the primary colors are cyan, magenta,and yellow. Other sets include the RYB system of red, yellow, blue, especially used by artists. 

For additive combination of colors, as in overlapping projected lights or in television and computer screens, the primary colors normally used are red, green, and blue.

Biological basis 
Primary colors are not a fundamental property of light but are related to the physiological response of the eye to light (the way the eye works). For humans, three primary colors are usually used, since human color vision is trichromatic.
The additive primaries are red, green,
and blue. Because of the response curves of the three different color receptors in
the human eye, these colors are optimal in the sense that the largest range
of colors — a gamut — visible by humans can be generated by mixing light of these colours.
Additive mixing of red and green light, produce shades of yellow or orange. Mixing green and blue produces shades of cyan, and mixing red and blue produces shades of purple and magenta. Mixing equal proportions of the additive primaries results in shades of grey; when all three colors are fully saturated, the result is white. The color space that is generated is called the RGB ("red, green, blue") color space.

Subtractive primaries
Media that use reflected light and colorants to produce colors are using the subtractive color method of color mixing. In the printing industry, to produce the varying colors, apply the subtractive primaries yellow, cyan, and magenta together in varying amounts. Subtractive color works best when the surface or paper, is white, or close to it.

Mixing yellow and cyan produces shades of green; mixing yellow with magenta produces shades of red, and mixing magenta with cyan produces shades of blue. In theory, mixing equal amounts of all three pigments should produce shades of grey, resulting in black when all three are fully saturated, but in practice they tend to produce muddy brown colors. For this reason, a fourth "primary" pigment, black, is often used in addition to the cyan, magenta, and yellow colors.
The color space generated is the so-called CMYK color space. The abbreviation stands for "Cyan, Magenta, Yellow, and Black" — K stands for "Kohle" (German for coal) and is used to represent black as 'B' could be confused with 'Blue'.

In practice, mixtures of actual materials like paint tend to be less precise. Brighter, or more specific colors can be created using natural pigments instead of mixing, and natural properties of pigments can interfere with the mixing. For example, mixing magenta and green in acrylic creates a dark cyan - something which would not happen if the mixing process were perfectly subtractive.

Reference 

Color
The umbilicus (also called navel or bellybutton) is a place on the body of mammals that is left after a baby loses its umbilical cord. The umbilicus of humans is in the middle of the abdomen. It is usually only easy to see on humans, and is a thin line on many other mammals. In humans, they can be split into two different kinds, the kind that goes in (innie) and the kind that goes out (outie). Different people have different navels that can be different in size, shape, and looks, but these differences are not genetic (you do not get them from looks passed down in your family). The hepatic portal vein passes from the umbilical vein to the liver. When a person becomes fat, the fat usually goes around the umbilicus.

It marks the water shed line of the body. The venus blood & lymph do not cross the umbilical plane.

Gallery

See also
 Navel piercing

Other websites

Torso
Captain James Cook, FRS (27 October 1728 – 14 February 1779) was a British explorer, navigator and cartographer. He sailed through the Pacific Ocean three times, mapped many areas and recorded several islands and coastlines on European maps for the first time. He was the first British sailor to visit both the east coast of Australia and the Hawaiian Islands. He made the first European maps of Newfoundland and New Zealand.   

He sailed twice around the world. He crossed the Antarctic Circle and visited islands and landscapes in North America and the South Pacific. During his trips, he spent a lot of time on science experiments and improving maps. He also wrote many books about what he found.
Life 
Cook was born on 27 November 1728 in Marton, Yorkshire, England. He was a son of a Scottish farmer. He was educated at the school in Great Ayton and at 17 he began work in a shop at Staithes. At 18, Cook became a sailor and an apprentice to John Walker of Whitby. Walker's business was transporting coal. Cook learned mathematics and navigation from Walker. He studied as much as he could about navigation and science.

In 1755, he joined the Royal Navy. During the Seven Years' War, he participated in the conquest of Canada. After the war, he was sent on three expeditions that all over the world with the ship Endeavour.

His goals on these missions were:
 to find the unknown southern continent (Terra australis incognita)
 to make astronomical measures of Venus
 to map new lands
 to take over the land for King George III
 to watch for good places for new military bases
 to find new routes between the Pacific Ocean and the Atlantic Ocean
to establish an observatory in Tahiti
Cook was killed in the Hawaiian Islands in a dispute about a stolen boat.

Cook's Family 
He had four sons and one daughter. Their names were Elizabeth Cook, Hugh Cook, George Cook, Nathaniel Cook and Joseph Cook.

His father, James Cook, had three sisters and two brothers. Their names were Mary Cook, who died at four; Margaret Cook; William Cook; Jane Cook and John Cook.

References 

1728 births
1779 deaths
English explorers
English murder victims
Exploration of Australia
Murders by blade weapons
People from Middlesbrough
British sailors
The offside rule is one of the oldest football rules, but is still a much discussed rule. This is probably because of the relatively complicated set of provisions provided by the sport's law-making body, the IFAB for deciding if a player in an offside position is actually guilty of an offside offence by becoming involved in active play.  It can also be a difficult decision for the referee or assistant referee to make as they need to watch the ball, the player playing the ball and also the attacker who is seeking to receive the ball at the same time.
Offside is an offence committed by the team which has the ball and is punished with an indirect free kick.
It is a common misconception that the ball must be played forward for an offside offence to be committed. This is incorrect however, as an offside offence is related to the position of the player in relation to the last two opponents, the ball and the opponent's goal line rather than the direction the ball is played. If the player is closer to the opponent's goal line than both the ball and the second-last opponent when it is played by a team mate, she or he is in an offside position.
But there are some exceptions:
 Players cannot be offside in their own half of the field.
 It is not possible to be offside from a throw-in, corner kick or goal kick.
 If the ball is deliberately played by a member of the opposing team, an attacker cannot be offside.
 A player who is behind the other team's goal line is considered to be on the goal line for the purposes of offside. It is an offence to leave or re-enter the field of play without permission but not if it is part of a natural playing movement.
 If the player is behind the ball when it is played, he or she cannot be offside.
 An attacker who is exactly in line with the 2nd last defender or the ball is not considered to be offside.
If a player does not become involved in active play, then it is not an offside offence even if that player is in an offside position (the concept of passive offside introduced in 1924). A player can become involved in active play by touching the ball (either directly from a team mate's touch or after it rebounds off the goal frame or an opponent) or interfering with another player's ability to play the ball.
References

Football (soccer) terminology
Valentine's Day is a celebration that happens on February 14. It is the day of the year when lovers celebrate their love. This can be done by giving flowers, chocolates, Valentine's cards or just a nice gift.  Love notes can be given to one another.  These notes that people give out are also called valentines.   Some people pick one person and call them their "Valentine" as a gesture to show love and appreciation.

Symbols of Valentine's Day are heart shapes, roses, and Cupid with his arrows.

Valentine's Day is named for the martyred Christian saint named Valentine. He was a bishop that performed marriages between forbidden couples.

Since the 14th century, Valentine's pairs are formed in England. English emigrants then took the Valentine's custom to the United States. After  World War II, US soldiers brought this festival to Europe.
Legend 
In the third century A.D., Valentine was the bishop of Terni (Italy). He performed weddings for couples who were not allowed to get married. They may not have been allowed to get married because the parents did not agree with the connection or because the bridegroom was a soldier or a slave, so the marriage was forbidden. Valentine gave the married couple flowers from his garden. That's why flowers play a very important role on Valentine's Day. This did not please the emperor. On February 14, 269 AD, Valentine was beheaded because of his Christian faith.
United States and Europe 
In the 19th century, the custom of sending Valentine's Cards became very popular. The cards usually have pictures of hearts or flowers and contain some sort of poem, message, or code. Codes and simple messages give some people the courage to show their true feelings to the person they love. Today, some people still use mysterious codes to show their love. People can use newspapers to give a coded message to their loved one, giving other readers a view of the couples' intimacy with one another. Sometimes they will give each other chocolates.

Famous for the popularity of the celebration is the folk song called "Die Vogelhochzeit" ("The Birds' Wedding").

China 

In China, a holiday called Qi Xi is also called "Chinese Valentine's Day", especially by younger people. Qi Xi is traditionally held on the 7th day of the 7th month of the lunar calendar. In recent years, it has become more like Valentine's Day in other countries.

References 

Observances
February events
The Canary Islands are a group of islands off the coast of Morocco. They are an autonomous community of Spain (they make their own laws). There are seven main islands. The people who live there speak Spanish. The autonomous community has two capital cities, of equal status: Santa Cruz de Tenerife and Las Palmas de Gran Canaria. Like the other islands of Macaronesia, they were created by volcanoes on the bottom of the sea. Those volcanoes slowly rose above the water and became islands. This process lasted many thousands of years.

The islands have a very long and interesting history. When Europeans first came to the Canary Islands, they found people already living there. These people were called the Guanches.  Many of the Guanches were killed in 15th-century battles with the Spanish, and the ones who remained adopted the Spanish way of life.  After the Spanish conquest, many battles were also fought against pirates.  Most recently Morocco was interested in them.
After the Spanish conquest, many Europeans settled there. Portuguese and Spaniards, and also Belgians and Maltese were among the early settlers. Recently many people from all over Europe, America, India, and Africa have also become citizens or permanent residents.

The seven islands are: La Palma, La Gomera, El Hierro, Tenerife, Gran Canaria, Lanzarote, and Fuerteventura. People from La Gomera have a whistle language that children there learn at school. Tenerife has the highest mountain in the Canary Islands and Spain too, the Teide. The Teide is actually a volcano, but it has not been active in more than 300 years. 

The islands are popular with tourists because of their warm climate and nice beaches. The local farmers grow lots of exotic fruits including papayas and bananas.

The Canary Islands' main exports include bananas and tobacco.

References

Other websites
 
 

Archipelagos
 
North Africa
Edinburgh Airport (IATA EDI, ICAO: EGPH) is an airport in Scotland. It is one of seven airports in the United Kingdom owned by the company BAA, which also owns Glasgow Airport and Aberdeen Airport in Scotland.
 It is served by many different airlines including Scot Airways, British Airways, EasyJet, BMI, Continental Airlines, Air France, and Lufthansa. The airport has good road links to the city centre with a bus running every 10 minutes from the airport to the centre of Edinburgh, a number of taxis are always available. Just over 9 million people a year use the airport, but there are plans to make the airport bigger in the future.

On 19th October 2011, BAA Limited said that it is going to sell Edinburgh Airport. This was done following a decision by the UK's Competition Commission which said that BAA needs to sell either Glasgow or Edinburgh Airport.
Accidents
In February 2001 a Shorts 360 crashed shortly after taking off from Edinburgh Airport. Both pilots were killed but there were no passengers on board as it was a mail-carrying flight.

References

Other websites 
 Edinburgh Airport official website
Airports in Scotland

Buildings and structures in Edinburgh
Lufthansa is the largest airline in Germany, and the second-largest in Europe. Some of Lufthansa's hubs are Frankfurt am Main and Munich, Germany. A hub is an airport where people who fly from one city to a second city can transfer or change airplanes.

Lufthansa buys airplanes from Boeing and Airbus. Lufthansa has big airplanes for flights to North America, Asia, and Africa. These flights are called long-haul flights because they are between cities that are far apart from each other. Lufthansa also has small airplanes for flights in Europe. These flights are called short-haul flights.

Lufthansa is a member of the Star Alliance, which means it is a partner with other airlines like United Airlines and Air Canada. Members of the Star Alliance cooperate or work together to schedule their flights better so that travelling is easier for passengers or people.
The name of Lufthansa's frequent flyer program is Miles and More. People earn points for flights they travel on. When they have enough points, they can get a free flight. Lufthansa has "Miles and More" to encourage people to fly with Lufthansa.

Many regional flights are operated Lufthansa Regional with Lufthansa CityLine, Eurowings and Air Dolomiti.

Fleet 

Lufthansa uses these airplanes:

Gallery

References

Other websites 

 Lufthansa website 

Article has been lengthened.

Star Alliance
Airlines of Germany
IATA members
1950s establishments in Germany
Transport in Germany
Orlando Jonathan Blanchard Bloom (born 13 January 1977, in Canterbury, Kent, England) is an English actor. He is most known for his first major movie role as the elf Legolas Greenleaf in The Lord of the Rings movie trilogy.

In 1993, he moved to London to improve his career, doing bit parts in TV series like Casualty. Then he played some theatres like The Seagull, Twelfth Night, and Trojan Women. This is a role that he received some days before graduating the drama school in London.
Movies 
Here are some movies, in which he played an important character:
 Wilde (1997)
 The Lord of the Rings: The Fellowship of the Ring (2001)
 Black Hawk Down (2002)
 The Lord of the Rings: The Two Towers (2002)
 Ned Kelly (2003)
 The Calcium Kid (2003)
 Pirates of the Caribbean: The Curse of the Black Pearl (2003)
 The Lord of the Rings: The Return of the King (2003)
 Troy (2004)
 Haven (2004)
 Kingdom of Heaven (2005)
 Elizabethtown (2005)
 Pirates of the Caribbean: Dead Man's Chest (2006)
 Pirates of the Caribbean: At World's End (2007)
 The Hobbit: The Desolation of Smaug (2013)
 The Hobbit: The Battle of the Five Armies (2014)
 Pirates of the Caribbean: Dead Men Tell No Tales (2017)

Other websites 

 

1977 births
Living people
Actors from Kent
English movie actors
English television actors
Canterbury
871 was a common year.

Events 
Somerton becomes the capital of the Kingdom of Wessex.
Alfred the Great succeeds as king of Wessex after Ethelred of Wessex's death.
Events 
 January 25 – The British Parliament passes the Constitutional Act of 1791, splitting the province of Quebec (a colony in North America spreading from the Gulf of Mexico coast to Hudson Bay)
 March 2 – A semaphore machine is revealed to the public in Paris.
 March 4 – Vermont becomes a state in the United States.
 May 3 – The Polish-Lithuanian Commonwealth Sejm (Parliament) proclaims the Constitution of third May, the first modern codified, or legal code-like, constitution in Europe.
 July 14 – The Priestley Riots happen in Birmingham, West Midlands, England.
 June 20 – The French Royal Family is captured when they try to flee in disguise.
 July 17 – The Champ de Mars Massacre occurs during the French Revolution.
 August 4 – The Treaty of Sistova is signed, ending the Ottoman-Habsburg wars.
 August 6 – Brandenburg Gate in Berlin is finished.
 August 26 – John Fitch is given a patent for the steamboat in the United States.
September 25 – The Mission Santa Cruz is founded by Father Fermín Francisco de Lasuén, becoming the twelfth mission in the California mission chain.
 September 30 – First showing of Wolfgang Amadeus Mozart's singspiel, a type of opera, Die Zauberflöte (Magic Flute) in the Freihaustheater in Vienna.
 October 9 – The Mission Nuestra Señora de la Soledad, was founded by Father Fermín Francisco de Lasuén, becoming the thirteenth mission in the California mission chain.
 December 4 – The first issue of The Observer, the world's first Sunday newspaper, is published.
 December 15 – The states approve ten amendments to the United States Constitution, which become the Bill of Rights. Two additional amendments are still being thought about, and one of these is finally approved in 1992, becoming the Twenty-seventh Amendment.
Undated Events 
 The first American ship reaches Japan.
 Slave rebellion Haiti has begun.
Births 
 January 15 – Franz Grillparzer, Austrian writer (d. 1872)
 January 28 – Louis Joseph Ferdinand Herold, French composer (d. 1833)
 February 12 – Peter Cooper, American Industrialist, inventor and philanthropist (d. 1883)
 February 21
 Carl Czerny, Austrian composer (d. 1857)
 John Mercer, chemist and industrialist (d. 1866)
 April 23 – James Buchanan, 15th President of the United States (d. 1868)
 April 27 – Samuel Morse, American inventor (d. 1872)
 July 26 – Franz Xaver Wolfgang Mozart, Austrian composer and pianist (d. 1844)
 September 5 – Giacomo Meyerbeer, German composer (d. 1864)
 September 21 – István Széchenyi, Hungarian politician and writer (d. 1860)
 September 22 – Michael Faraday, British scientist (d. 1867)
 September 26 – Théodore Géricault, French painter (d. 1824)
 November 11 – Josef Munzinger, member of the Swiss Federal Council (d. 1855)
 December 26 – Charles Babbage, British mathematician and inventor (d. 1871)
Deaths 
 January 11 – William Williams Pantycelyn, Welsh hymnist (b. 1717)
 March 2 – John Wesley, English founder of Methodism (b. 1703)
 March 14 – Johann Salomo Semler, German historian and Bible commentator (b. 1725)
 April 19 – Richard Price, Welsh philosopher (b. 1723)
 May 9 – Francis Hopkinson, American signer of the Declaration of Independence (b. 1737)
 June 5 – Frederick Haldimand, Swiss-born British colonial governor (b. 1718)
 June 10 – Toussaint-Guillaume Picquet de la Motte, French admiral (b. 1720)
 July 17 – Martin Dobrizhoffer, Austrian Jesuit missionary (b. 1717)
 July 25 – Isaac Low, American delegate to the Continental Congress (b. 1735)
 August 16 – Charles-François de Broglie, marquis de Ruffec, French soldier and diplomat (b. 1719)
 November 4 – Richard Butler (general), American soldier (b. 1743)
 September 25 – William Bradford, American printer (b. 1719)
 December 5 – Wolfgang Amadeus Mozart, Austrian composer (b. 1756)

1791
Year 1084 (MLXXXIV) was a leap year starting on Monday (link will display the full calendar) of the Julian calendar.

Events 
 May – Sack of Rome by the Normans of Robert Guiscard.

Births 
 David I of Scotland
Chromium is a chemical element. Its symbol on the periodic table (a list of all the elements) is Cr. It always has 24 protons, so its atomic number is 24. Its mass number (number of protons and neutrons) is about 54. Most of the times it has 28 neutrons, but different isotopes have more or fewer neutrons. As a metal, it has 24 electrons. Its ions have fewer electrons.

Properties
Chromium is a shiny metal. It is reactive, but it reacts with air to produce a very thin coating of chromium(III) oxide, which prevents it from rusting any more.
Compounds
Chromium occurs in several oxidation states; +2, +3, and +6 are most common. It forms chemical compounds that are colorful.
Chromium(II) oxide, black, rare, reducing agent
Chromium(II) chloride, blue when dissolved in water, unstable
Chromium(III) oxide, dark green
Chromium(III) chloride, green when containing water (hydrated), purple when not containing water (anhydrous)
Chromium(III) sulfate
Chromium(IV) oxide, black, used in cassettes
Chromium(VI) oxide, chromium trioxide, red, oxidizing agent, toxic. Chromic acid is formed by dissolving chromium(VI) oxide in water.
Chromyl chloride, red liquid
Chrome alum
Trivalent chromium
There are two main types of chromium ions, which are found in chromium compounds. One type of chromium ion (Cr3+, trivalent chromium ) is required by our body and by those of other animals. If we do not get enough chromium, certain parts of our body may not work properly. We get most of the chromium we need from our food we eat. Chromium is also put into vitamins to make sure that we get enough. If we get too much of this type of chromium, it can harm our body.

Hexavalent chromium
Another type of chromium (Cr6+ (chromate, hexavalent chromium), in the +6 oxidation state) can cause cancer or make people sick, even though most people do not get exposed to it much. It is found in places that make chromium metal, which is why they need to be cleaned up when they close. Hexavalent chromium can be destroyed by reacting it with reducing agents, turning it into Cr3+ (trivalent chromium). They are strong oxidizing agents.
Chromates
The chromate ion is CrO42-. Chromates are generally yellow.
Potassium chromate
Sodium chromate

Dichromates
The dichromate ion is Cr2O72-. Dichromates are red or orange.
Ammonium dichromate
Potassium dichromate
Sodium dichromate, used in chromium processing

Occurrence and preparation

Chromium occurs as chromite. Chromite is a mixture of iron(II) oxide and chromium(III) oxide. Its chemical formula is FeCr2O4. It is heated with sodium carbonate to make sodium chromate, iron(III) oxide, and carbon dioxide. The sodium chromate is reacted with sulfuric acid to produce sodium dichromate. The sodium dichromate is reduced by carbon to chromium(III) oxide. The chromium(III) oxide is reacted with aluminum to make chromium metal. The chromates and dichromates are what make chromium production areas toxic.
Uses
Chromium is used in different metal products. Stainless steel is the most common use. It is also used in "chrome plating", where it makes things shiny and stops corrosion. Some chromates were used as pigments, but they are toxic so people do not want to use them anymore.

Safety
Chromium metal is nontoxic. But hexavalent chromium is toxic and carcinogenic, and trivalent chromium is mildly toxic in large quantities.

Related pages
Chromium compounds

Transition metals
Neon is a chemical element on the periodic table.  It is part of the noble gas group and it has an atomic number of 10. It is an odorless and tasteless gas.  Neon does not react with other elements, so it is found by itself. There is not much neon in the air, and it is clear, so we do not see it.

It was previously thought that Neon could not bond with any other elements, creating compounds. However, there have been a few compounds that have been made with neon, such as NeAuF and NeBeS.
History 
Two British scientists, Sir William Ramsay and Morris Travers, discovered neon, argon, krypton, and xenon.  Together they discovered a brand new gas element in 1898.  Four years before, Ramsay, a physical chemist, had found argon and was the first person to isolate helium in 1895.  The scientists froze argon, using liquid air, and then evaporated this to collect the gas that is produced.  Using a high voltage, they collected the first sample of the gas.  To their surprise, the gas illuminated the glass tubes and glowed with bright crimson light.

Upon discovery, the two scientists decided to name the new gas Neon, after the Greek word Neos, meaning the new one. While Ramsay and Travers discovered neon gas, they didn’t invent neon lamps. It wasn’t until 1902 when French engineer and inventor Georges Claude showcased the first neon light.
Uses 
Neon gas is used in gas discharge lamps. When electricity goes through the neon, it lights up red. Due to this quality, it is used in light up signs. Similar signs use other gases to make other colors, but they are also often called "neon signs". Neon is also a term referring to a type of color that is very bright, such as lime green.

Related pages
List of common elements
 Neon lamp

References

Noble gases
Tin is a chemical element with symbol Sn (for ) and atomic number 50. It is in Group 14 on the periodic table. It has ten isotopes that are not radioactive, which is more than any other element.

Properties

Physical properties

Tin is a silver, somewhat soft metal. It is a post-transition metal. Its melting point is 231.93°C and its boiling point is 2602 °C. It can melt easily in a flame. It is malleable. It makes a crackling sound called tin cry when a piece of it is bent. Tin has more non-radioactive isotopes than any other element.
Tin is found in two allotropes: alpha-tin and beta-tin. Alpha-tin is a brittle, dull, powdery, semimetallic form of tin. It is made when very pure tin is cooled. Beta-tin is the normal shiny, soft, conductive, metallic form. It is made at higher temperatures. The decay of tin by turning from beta-tin to alpha-tin is called tin pest. Alpha-tin is not wanted in many places. When small amounts of other elements like antimony are added, the tin cannot change into alpha-tin. When alpha-tin is heated, it changes into beta-tin.

Tin can be hardened by adding antimony or copper, as well as some other elements. These also make it resistant to tin pest. Tin can also be made very shiny. Tin can make an alloy with copper called bronze.

Chemical properties

Tin resists many corrosive substances and is often used to protect other metals.  Salt water and fresh water do not affect tin.  It dissolves in strong acids to make tin salts.  It reacts with some strong bases.

Chemical compounds
Chemical compounds

Tin forms chemical compounds in two oxidation states: +2 and +4. +2 compounds are reducing agents. Some of them are colorless while others are colored. +4 compounds are more unreactive and act more covalent.

Tin burns in air to make tin(IV) oxide, which is white. Tin(IV) oxide dissolves in acids to make other tin(IV) compounds. Tin(IV) chloride is a colorless fuming liquid when anhydrous and a white solid when hydrated. It easily reacts with water to make tin(IV) oxide and an acid again.

Tin reacts with hydrohalic acids to make tin(II) halides. For example, tin(II) chloride is made when tin dissolves in hydrochloric acid. Tin(IV) halides are made when tin reacts with the halogens. Tin(IV) chloride is made when tin reacts with chlorine. Tin(II) sulfate is different as it does not oxidize to tin(IV) sulfate. Tin(II) oxide is a blue-black solid that burns in air to make tin(IV) oxide.
+2 compounds
+2 compounds are reducing agents. They are about as common as +4 compounds. Some are colorless, while others are colored.
Tin(II) bromide, yellowish solid
Tin(II) chloride, white solid
Tin(II) fluoride, white solid
Tin(II) iodide, orange solid
Tin(II) oxide, blue-black solid
Tin(II) sulfate, white solid
Tin(II) sulfide, dark brown solid

+4 compounds
+4 compounds are unreactive. Some are colorless.

Tin(IV) bromide, colorless solid
Tin(IV) chloride, colorless liquid or solid
Tin(IV) fluoride, colorless solid
Tin(IV) iodide, orange solid
Tin(IV) oxide, colorless solid
Tin(IV) sulfide, gold-colored solid

Occurrence

Tin is not found as a metal in the ground. It is normally in the form of cassiterite. Cassiterite is a mineral containg tin(IV) oxide. The cassiterite is normally found downstream of the cassiterite deposit when it is by a stream or river. Tin is also found in some complicated sulfide minerals.

Tin does not have any major job in the human body.
Preparation
Tin is made by heating cassiterite with carbon in a furnace. China is the biggest maker of tin.

History
People discovered tin long ago and used it with other metals.  When copper and tin are mixed together, bronze is made. Bronze was important in the past, because it was one of the strongest metals available, which meant it was useful in weapons and tools. Bronze changed the world when it was first invented, starting the Bronze Age. People organized themselves more, because making tools from bronze was harder than making them from rock and wood like they did before.

Uses

Tin is used in solder. Solder used to contain a mixture of lead and tin. Now the lead is removed because of its toxicity.
Tin is also used to make pewter, which is mainly tin mixed with a small amount of copper and other metals. Babbitt metal also has tin in it. Tin is used to coat several metals, like lead and steel. Tin plated steel containers are used to store foods. The pipes on a pipe organ are made of tin. Tin foil was used before aluminium foil. Tin was one of the first superconductors to be found. Organotin compounds are more common than almost any other organometal compound. They are used in some PVC pipes to stop them from decaying. Organotin compounds are toxic, though.

Safety
Tin is not toxic, but tin compounds are very toxic to marine life. They are a little toxic to humans.

Sources

Post-transition metals
Silicon is a chemical element. Its atomic number is 14 on the periodic table. Its symbol is Si. It is a hard, brittle crystalline solid. It is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic table.

Silicon looks like a metal, but cannot do everything that a metal can, like conduct electricity well. Silicon is used a lot in today's computers and nearly every other electronic device as well. Germanium can also be used in computers, but silicon is much easier to find. 

For example, all of the sand found at the beach is made of small cubes of  silicon dioxide also known as  silica. Glass is made by heating sand hot enough until it melts. Glass made from silicon can be made in different colours by adding colouring compounds. Many rocks and minerals are composed of compounds of silicon and oxygen called silicates.
Silicon in computers 
Silicon is a semiconductor, and much used in computers. A super-pure isotope of silicon, silicon-28, can now be made 40 times more pure than before. It is very important for the next big development in computers. This stores "qubits" in atoms of another element, like phosphorous, embedded in a tiny layer of ultra-pure silicon-28. These qubits can simultaneously encode a one and a zero, for incredibly fast and complex calculations.

Related pages
 List of common elements

References 

Semimetals
Cadmium is a metal. It is element 48 on the periodic table. Its symbol is Cd. Its atomic number is 48 and its atomic mass is 112.4. It is found in Group 12 on the periodic table.

Properties

Physical properties
Cadmium is a blue-gray soft metal. It can be considered a transition metal or a post-transition metal. It is malleable and ductile. It is similar to zinc. It melts at 321°C.

Cadmium has 8 natural isotopes. 5 are radioactive, but 3 have very long half-lives so their radioactivity is almost nothing.

Chemical properties
Cadmium is a moderately reactive metal. It corrodes in moist air and dissolves in acids. It burns in air when powdered to make the brown cadmium oxide.

Chemical compounds
Chemical compounds

Cadmium forms chemical compounds in two oxidation states: +1 and +2. The +1 state is rare and unstable. The +2 state is much more common. Most +2 compounds dissolve easily in water and are white to yellow. Cadmium oxide can be brown, red, or white. Cadmium sulfide is bright yellow. Cadmium chloride and cadmium sulfate are colorless solids that dissolve easily in water. Cadmium fluoride is slightly soluble. Cadmium compounds are toxic when inhaled.

Cadmium bromide, pale yellow solid, dissolves in water
Cadmium chloride, colorless solid, dissolves in water
Cadmium fluoride, gray solid, does not dissolve good in water
Cadmium iodide, pale yellow solid, dissolves in water
Cadmium oxide, white, brown, or red solid, dissolves in acids
Cadmium sulfate, colorless solid, dissolves in water
Cadmium sulfide, bright yellow solid, does not dissolve in water
Cadmium telluride, black solid, semiconductor
History
Cadmium was found by two chemists, German chemist Friedrich Stromeyer discovered it in 1817, and Karl Herman also discovered it in 1818. They were looking at an impurity in zinc carbonate and found cadmium. For about 100 years, Germany made most cadmium. Cadmium iodide was used as a medicine although it was toxic.

Occurrence

Cadmium ores are rare. Greenockite, a cadmium sulfide mineral is the only main ore and it is found with sphalerite, a zinc sulfide. Because of this, most cadmium comes from zinc processing. Cadmium as a metal is very rare but is found in one place in Russia.

Preparation
China makes the most cadmium. South Korea and Japan also make cadmium. Cadmium is taken from the zinc metal by heating the zinc metal in a vacuum. Cadmium is boiled first. The cadmium is condensed and used. Cadmium is also taken by precipitating it from the solution of zinc sulfate used to make pure zinc by electrolysis.
Uses
In the 1930s and 1940s cadmium was mainly used to plate steel to prevent it from corroding. Then cadmium sulfide was used as a pigment in paint. 

Now, cadmium is mainly used in nickel cadmium batteries. 86% of cadmium is used in batteries as of 2009. Some people are trying to stop using nickel-cadmium batteries because cadmium is toxic. Cadmium is still used to electroplate steel to prevent corrosion. Only about 6% of cadmium is used for this. Cadmium is also used in lasers, nuclear reactors, phosphors, photoresistors, pigments, and semiconductors. Wood's metal, an alloy that melts very easily, has cadmium in it. Cadmium is used in some solder. 

Cadmium is not used in the human body or any other animal. A diatom uses cadmium, though.
Safety
Cadmium is a highly toxic metal. Dust of cadmium or its compounds is very dangerous and can kill. Some countries have banned cadmium from electronics. Cigarette smoking is the most important source of cadmium. Smokers have about 4 times more cadmium in their blood than nonsmokers (people who do not smoke). Cadmium is thought to be carcinogenic, although people still debate whether it is other things with the cadmium that cause cancer, like arsenic.

References

Transition metals
Krypton is a stable noble gas. It has an atomic number of 36. The name krypton comes from the Greek word kryptos meaning hidden. It is used in fluorescent lamps, flashbulbs, and as a wavelength standard. The metre used to be defined as 1,650,763.73 wavelengths in a vacuum of krypton gas.

Chemistry 
Because it is a gas, it does not react with many elements. It is clear and has no taste or smell. The atmosphere is only about one millionth part krypton. Krypton has very few compounds.