butene: cis-2-butene, trans-2-butene, and isobutylene. All four butenes are gases at room temperature and pressure.

isopropyl alcohol, one of the most common members of the alcohol family of organic compounds. Isopropyl alcohol was the first commercial synthetic alcohol; chemists at the Standard Oil Company of New Jersey (later Exxon Mobil) first produced it in 1920 while studying petroleum by-products. It is

acetone (CH3COCH3), organic solvent of industrial and chemical significance, the simplest and most important of the aliphatic (fat-derived) ketones. Pure acetone is a colourless, somewhat aromatic, flammable, mobile liquid that boils at 56.2 °C (133 °F). Acetone is capable of dissolving many fats

aldehyde: Nomenclature of aldehydes: …IUPAC name is 2-propenal, is acrolein, a name derived from that of acrylic acid, the parent carboxylic acid.

acrylamide, a white, odourless, crystalline substance belonging to the family of organic compounds; its molecular formula is C3H5NO. Acrylamide is produced as a result of industrial processes and is generated in certain foods as a result of cooking at high temperatures. Because acrylamide is

Two-Tone Movement: In several regional British cities, the distinct late 1970s combination of economic turmoil, unemployment benefits (effectively an arts subsidy), and art school punks resulted in a generation of eccentric talent. In Coventry, the southernmost centre of Britain’s Midlands engineering belt, the outcome was 2-Tone, a…

Two-Tone Movement: … engineering belt, the outcome was 2-Tone, a mostly white take on ska, the music brought to Britain by Jamaican immigrants in the mid-1960s and favoured by English mods of the period, whose two-tone Tonik suits gave the latter-day movement its name. In 1977 art student Jerry Dammers founded the Specials,…

List of Highest-Grossing Indian Films: …Dutt 792 (about $125 million) 2.0 2018 S. Shankar Rajinikanth, Akshay Kumar, and Amy Jackson 691 (about $101 million) Gadar 2 2023 Anil Sharma Sunny Deol, Ameesha Patel, and Utkarsh Sharma 686 (about $83 million) Baahubali: The Beginning 2015 S.S. Rajamouli

number symbolism: 20: The number 20 has little mystical significance, but it is historically interesting because the Mayan number system used base 20. When counting time the Maya replaced 20 × 20 = 400 by 20 × 18 = 360 to approximate the number of days in…

From the Rose Seidler House and Mooloomba House to the Sydney Opera House, these 20 buildings are examples of some of Australia’s most architecturally and historically important structures. Earlier versions of the descriptions of these buildings first appeared in 1001 Buildings You Must See Before

Storms, which are turbulent atmospheric disturbances, are among the most destructive natural forces and can cause tremendous loss of life and devastation—from flooding and damage to trees, unanchored structures, and power lines to the obliteration of well-built structures. Storms are marked by

History of film: United States: …of a white woman; and 20 Feet from Stardom, (2013), Morgan Neville’s exploration of the lives of backup singers.

Amelia Earhart: Historic flights: …wrote about the flight in 20 Hrs. 40 Min. (1928) and undertook a lecture tour across the United States. Much of the publicity was handled by publisher George Palmer Putnam, who had helped organize the historic flight. The couple married in 1931, but Earhart continued her career under her maiden…

In the early 1990s, an intact mummy was discovered in the Ötztal Alps, on the Italian-Austrian border, that proved to be more than 5,000 years old. What is known today as Austria has been populated for a very long time; the buildings here are just a blip on the region’s history, but they’re all

The origins of the Museo del Prado, or Prado Museum, can be traced back to 1785, when the building in Madrid that the Prado now occupies was commissioned by King Charles III. The museum contains the most complete collections in the world of the works of El Greco, Velázquez, and Francisco de Goya,

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner. And if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

The future is unwritten. It is also right around the corner, and, if, as science fiction author William Gibson noted, it is not evenly distributed, more and more young people around the world are reaching toward it to shape it, improve it, and make it more equitable. These “shapers of the future”

20,000 Leagues Under the Sea, American dramatic film, released in 1954, that was the acclaimed adaptation of Jules Verne’s classic nautical adventure of the same name. Kirk Douglas, Peter Lorre, and Paul Lukas played the hapless trio of seamen who, while attempting to investigate a string of

Michael Curtiz: The breakthrough years: With 20,000 Years in Sing Sing, he infused the tired prison film genre with a new drive, making the most of Spencer Tracy as a doomed inmate and Davis as his loyal moll. Even more impressive was Mystery of the Wax Museum, a quasi-sequel to Doctor…

TEU, standard unit for cargo capacity for container ships and ports. The TEU refers to a shipping container that measures 20 feet long (6.1 meters), 8 feet 6 inches (2.6 meters) high, and 8 feet (2.4 meters) wide. High-cube shipping containers have a height of 9 feet 6 inches (2.9 meters) and

John Stossel: …ABC (American Broadcasting Company) newsmagazine 20/20.

Justin Timberlake: Solo music career and acting roles: …he mounted a comeback with The 20/20 Experience, a pair of luxuriant song suites that were recorded in collaboration with Timbaland and released six months apart. Boasting both contemporary electronic production and nods toward old-fashioned R&B, The 20/20 Experience found Timberlake sounding relaxed and romantic, particularly on singles such as…

Casey Affleck: …films as Desert Blue (1998), 200 Cigarettes (1999), and Michael Almereyda’s modern-day adaptation of Hamlet (2000) before being cast as a member of the crew in the commercially successful caper comedy Ocean’s Eleven (2001), a role he repeated in Ocean’s Twelve (2004) and Ocean’s Thirteen (2007). Affleck drew favorable

Frank Zappa: Posthumous honors and legacy: …lyrics from Zappa’s motion picture 200 Motels (1971), this was no mean achievement. Similarly, an annual festival celebrating Zappa thrived in the early 21st century in Bad Doberan, Germany (formerly in East Germany), where his music had once been banned.

Usain Bolt: Early life and world junior championships: …the time—won gold in the 200 meters, becoming the youngest-ever male world junior champion in any event.

comic strip: Institutionalization: …market is exemplified in Britain’s 2000 ad, which flourished from 1978 to 1985 (and continues in the 21st century at a lower circulation level), was reprinted in the United States, and at its peak sold 120,000 copies per week. Its chief feature was Judge Dredd; written from a cynical perspective…

United States presidential election of 2000, American presidential election held on November 7, 2000, in which Republican George W. Bush narrowly lost the popular vote to Democrat Al Gore but defeated Gore in the electoral college. Gore, as Bill Clinton’s vice president for eight years, was the

Mel Brooks: Early life and work: …to bring to life “The 2,000 Year Old Man,” a mostly improvised bit that the duo performed in television appearances and on best-selling comedy record albums. Brooks entered the motion picture industry as the writer and narrator of the Academy Award-winning animated short The Critic (1963), a devastating lampoon…

2001 Mars Odyssey, U.S. spacecraft that studied Mars from orbit and served as a communication relay for the Mars Exploration Rovers and Phoenix. The 2001 Mars Odyssey was launched from Cape Canaveral, Florida, on April 7, 2001, and was named after the science fiction film 2001: A Space Odyssey

2001: A Space Odyssey, American science-fiction film, released in 1968, that set the benchmark for all subsequent movies in the genre and consistently ranks among the top 10 movies ever made, especially known for its groundbreaking special effects and unconventional narrative. The complex and

2001: A Space Odyssey, science fiction novel that was developed in tandem with the movie of the same name by American filmmaker Stanley Kubrick and English writer Arthur C. Clarke and published in 1968, shortly after the release of the movie. As Kubrick focused increasingly on the film, the visions

2002 Bali Bombings, terrorist attack involving the detonation of three bombs on the Indonesian island of Bali on October 11, 2002, that killed 202 people. At 11:05 pm a suicide bomb exploded in Paddy’s Bar, a locale frequented by foreigners, especially Australian youth. The bar’s patrons, some of

Bam: …was struck by a massive earthquake. The temblor, which had a moment magnitude of 6.6, killed more than 26,000 people and devastated the modern city, and the fortress itself was largely destroyed. Pop. (2011) 107,131; (2016) 127,396.

Haumea, unusual dwarf planet orbiting the Sun in the Kuiper belt beyond Pluto. It was discovered in 2003 by a team of American astronomers at Cerro Tololo Inter-American Observatory. Originally called 2003 EL61, Haumea is named for the Hawaiian goddess of birth and fertility. In September 2008 the

Eris, large, distant body of the solar system, revolving around the Sun well beyond the orbits of Neptune and Pluto in the Kuiper belt. It was discovered in 2005 in images taken two years earlier at Palomar Observatory in California, U.S. Before it received its official name, Eris was known by the

United States presidential election of 2004, American presidential election held on November 2, 2004, in which Republican George W. Bush was elected to a second term, defeating Democrat John Kerry, a U.S senator from Massachusetts. In the primary campaign, Bush faced little opposition for the

Makemake, dwarf planet orbiting the Sun beyond the orbit of Pluto. Originally called 2005 FY9, Makemake is named after the creator god of the Polynesian inhabitants of Easter Island; the name alludes to its discovery by astronomers at Palomar Observatory on March 31, 2005, a few days after Easter.

2006 Mumbai train bombings, terror attack in the form of serial blasts carried out on the Suburban Railway network (often referred to as “local trains”) in Mumbai on July 11, 2006. Seven coordinated explosions occurred on local trains over roughly 11 minutes during the evening rush hour, killing

American presidential election held on November 4, 2008, in which, after a campaign that lasted nearly two years, Americans elected Democrat Barack Obama their 44th president. The result was historic, as Obama, a first-term U.S. senator from Illinois, became, when he was inaugurated on January 20,

The candidates are listed in alphabetical order. For more information on each question and to see each candidate’s full statement, use the table of contents at the right or scroll down. In the table below, “nf” stands for “not found,” meaning the ProCon team has not found a statement from the

The 2009 Iranian presidential election protests marked a turning point in the history of Iran’s Islamic Republic. After the Islamic Revolution of 1979 the new government billed itself as democratic, but in the 1980s a conservative faction of Shiʿi Muslim clerics, led especially by the hawkish

Napoleon’s military prowess is legendary, and his victories made him the virtual master of continental Europe for more than a decade. His abdication in 1814 led to almost a year in exile on the island of Elba, but he returned triumphantly to France in March 1815. So began the Hundred Days, which

2010 Haiti earthquake, large-scale earthquake that occurred January 12, 2010, on the West Indian island of Hispaniola, comprising the countries of Haiti and the Dominican Republic. Most severely affected was Haiti, occupying the western third of the island. An exact death toll proved elusive in the

asteroid: Trojan asteroids: The first Earth Trojan asteroid, 2010 TK7, which librates around L4, was discovered in 2010. The first Uranus Trojan, 2011 QF99, which librates around L4, was discovered in 2011. Although Trojans of Saturn have yet to be found, objects librating about Lagrangian points of the systems formed by Saturn and…

Arthur C. Clarke: …Space Odyssey during this time: 2010: Odyssey Two (1982, filmed 1984) and 2061: Odyssey Three (1988).

German E. coli outbreak of 2011, bacterial disease outbreak that began in Germany in late April 2011 and that was caused by a previously rare strain of E. coli (Escherichia coli) known as O104:H4. The 2011 E. coli outbreak was the deadliest and the second largest on record—the largest was the Japan

Danny Glover: In the sci-fi thriller 2012 (2009) Glover played a U.S. president confronting a global catastrophe. He subsequently appeared in Death at a Funeral (2010), Tula: The Revolt (2013), Waffle Street (2015), Mr. Pig (2016), and Jumanji: The Next Level (2019). Glover made his feature-film directorial

2012 Benghazi attacks, assaults on a U.S. diplomatic compound and a nearby CIA annex in the city of Benghazi, Libya, on September 11–12, 2012, which resulted in the deaths of four Americans, including the U.S. ambassador to Libya—the first violent death of a U.S. ambassador since 1988. The incident

American voters went to the polls on November 6, 2012, to determine—for the 57th time—their country’s president for the next four years. Incumbent Democratic President Barack Obama’s reelection bid was, from the outset, expected to be closely contested as the United States faced a number of

ARCHIVED TOPIC: This topic was archived on January 22, 2013, and will no longer be updated. Presidential candidates tracked by ProCon must: The candidates are listed in alphabetical order. For more information on each question and to see each candidate’s full statement, use the table of contents at

outbreak of Ebola virus disease that ravaged countries in western Africa in 2014–16 and was noted for its unprecedented magnitude. By January 2016, suspected and confirmed cases had totaled more than 28,600, and reported deaths numbered about 11,300, making the outbreak significantly larger than

New Horizons: …by another Kuiper belt object, Arrokoth, on January 1, 2019. Arrokoth was found to be a contact binary—that is, two Kuiper belt objects that had merged together.

The final of the world’s premier one-day international (ODI) cricket contest, the Cricket World Cup, took place on March 29. Australia defeated New Zealand by seven wickets. Australia captured its fifth World Cup title while New Zealand made its first appearance in the final. The two countries

2015 FIFA corruption scandal, bribery and corruption scandal involving the Fédération Internationale de Football Association (FIFA), the governing body of international football (soccer). More than two dozen FIFA officials and their associates were implicated in a 24-year self-enrichment scheme

ARCHIVED TOPIC: This topic was archived on January 21, 2017, and will no longer be updated. Presidential candidates tracked by ProCon must: The candidates are listed in alphabetical order. For more information on each question and to see each candidate’s full statement, use the table of contents at

United States Presidential Election of 2016, American presidential election held on November 8, 2016, in which Republican Donald Trump lost the popular vote to Democrat Hillary Clinton by more than 2.8 million votes but won 30 states and the decisive electoral college with 304 electoral votes to

The 2016 World Series begins on October 25, and it promises to be one of the most-watched (and most-anxiety-inducing) Major League Baseball championships in baseball history. That’s because this series pits the teams with the longest title droughts in both the American League and the National

COVID-19, highly contagious respiratory illness, the cause of the COVID-19 pandemic. COVID-19 was first detected in 2019 in Wuhan, China. A large proportion of infections in China were undocumented before travel restrictions and other control measures were implemented in late January 2020. As a

coronavirus: SARS-CoV-2: The virus, later named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causes the disease COVID-19, which primarily affects the respiratory system and often presents with symptoms such as fever and cough. The virus spread rapidly, reaching multiple regions—including Asia, Europe, and North America—by early 2020 through…

COVID-19, highly contagious respiratory illness, the cause of the COVID-19 pandemic. COVID-19 was first detected in 2019 in Wuhan, China. A large proportion of infections in China were undocumented before travel restrictions and other control measures were implemented in late January 2020. As a

Sri Lanka: Growing debt and instability: On April 21, 2019—Easter morning—eight explosions occurred in the vicinity of churches and hotels, leaving hundreds dead and hundreds more wounded. Another blast occurred near a church the next day, while other explosive devices were discovered and neutralized before being detonated. Authorities, who had been warned about the attack about…

coronavirus: SARS-CoV-2: The virus, later named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causes the disease COVID-19, which primarily affects the respiratory system and often presents with symptoms such as fever and cough. The virus spread rapidly, reaching multiple regions—including Asia, Europe, and North America—by early 2020 through…

2020 Beirut explosion, deadly blast that took place on August 4, 2020, in Beirut and was one of the largest non-nuclear explosions in history. It was caused by the improper storage of ammonium nitrate in a port warehouse. The explosion killed 218 people, injured about 7,000, displaced some 300,000,

Mali: 2020 and 2021 coups and transitional administration: The coup, while cheered by many in Mali, was met with regional and international condemnation.

ARCHIVED TOPIC: This topic was archived on January 7, 2021, and will no longer be updated. Presidential candidates tracked by ProCon must: The candidates are listed in alphabetical order. For more information on each question and to see each candidate’s full statement, use the table of contents at

United States presidential election of 2020, American presidential election held on November 3, 2020, in the midst of the global coronavirus (SARS-CoV-2) pandemic, in which Democrat Joe Biden, formerly the 47th vice president of the United States, defeated the incumbent president, Republican Donald

Scott Morrison: The 2019 bushfires, the coronavirus pandemic, and the 2021 flooding: …rain that produced extensive destructive flooding, especially in New South Wales, where about 18,000 individuals had to be evacuated. Again, climate change appeared to have contributed to the calamity, this time by intensifying the effects of the La Niña weather pattern that typically increases rainfall as well as cyclone activity.…

Israel: Difficulty in coalition formation, frequent elections, and growing prominence of minority issues: Clashes between Palestinian protesters and Israeli police left hundreds injured. Hamas launched rockets toward Jerusalem in response, prompting an escalation in violence between Israel and Hamas to a level unseen since 2014. Nevertheless, a cease-fire was reached after 11 days, an unusually swift resolution.

2021 Myanmar coup d’état, maneuvering in Myanmar on February 1, 2021, in which power was seized from a democratically elected government and handed to the military. The coup was rejected by the civilian population and sparked civil disobedience, protests, and enduring armed resistance to military

2022 FIFA World Cup, international football (soccer) tournament that took place in Qatar from November 20 to December 18, 2022, and was contested by the men’s national teams of 32 countries. Argentina won its third World Cup victory in the tournament after defeating France in the final match. The

2022 FIFA World Cup, international football (soccer) tournament that took place in Qatar from November 20 to December 18, 2022, and was contested by the men’s national teams of 32 countries. Argentina won its third World Cup victory in the tournament after defeating France in the final match. The

Tonga: History of Tonga: …(65 km) north of Nuku‘alofa, erupted, spewing a mix of ash, gas, and steam more than 12 miles (about 20 km) into the air and covering Tonga in thick volcanic ash. The eruption generated a devastating tsunami, and significant flooding led to extensive damage in the island nation.

The 2022 Nobel Prize for Peace was awarded jointly to Ales Bialiatski, a Belarusian human rights activist and political prisoner; the Center for Civil Liberties, a Ukrainian organization that promotes democracy and civil society; and Memorial, a Russian human rights organization that was shuttered

2022 FIFA World Cup, international football (soccer) tournament that took place in Qatar from November 20 to December 18, 2022, and was contested by the men’s national teams of 32 countries. Argentina won its third World Cup victory in the tournament after defeating France in the final match. The

Brazil: The return of Lula: …and gold of Brazil’s flag, stormed the country’s Congress, presidential palace, and Supreme Court, wreaking havoc and destruction in the halls of Brazilian democracy in response to Lula’s inauguration roughly a week earlier.

Kahramanmaraş earthquake of 2023, an earthquake and a severe aftershock that struck near the border separating southern Turkey from northern Syria on February 6, 2023. The magnitude-7.8 earthquake was centered south of the Turkish city Kahramanmaraş. This was followed less than 12 hours later by a

2023 could be thought of as a sort of Rorschach test. For example, when you think of the year, what first comes to mind? Regardless, it was a year. Relive the moments, people, and predicaments of 2023 here. And here’s to

Taiwan: The Lai Ching-te presidency: …April 3, 2024, a major earthquake occurred in Taiwan, with the epicenter located near the mountainous county of Hualien. The 7.4-magnitude quake—Taiwan’s most severe in 25 years—killed at least 9 people and left 50 missing and more than 1,000 injured. Numerous buildings were severely damaged. Train tracks were damaged in…

ProCon Debate: Are the Olympic Games an Overall Benefit for Their Host Countries and Cities? ProCon Issue in the News: More than 100 Olympic athletes who participated in the recent 2024 Paris Summer Games have requested that their tarnishing medals be replaced, according to New York Times

The Paris Olympics officially began on July 26, 2024. Over the course of the next two weeks, some 10,500 athletes will compete in 329 events. The Games will feature a full roster of star athletes, and there will undoubtedly be a number of breakout stars. Who should be on your radar? Read on for our

This article was first published on July 15, 2024, as a preview of the 2024 Paralympic Games in Paris. The results of the Games can be found here. On August 28, 2024, the Paris Paralympic Games will officially begin. Over the course of 11 days, some 4,400 athletes will compete in 549 events in 22

ARCHIVED TOPIC: This topic was archived on Nov. 6, 2024, and will no longer be updated. Presidential candidates tracked by ProCon must: When a candidate officially drops out of the race, we will no longer add information about them to the site. As the election proceeds, the criteria may change to

United States presidential election of 2024, American election, held on November 5, 2024, in which former Republican president Donald Trump (2017–21) defeated the Democratic nominee, Vice Pres. Kamala Harris. Trump, who lost his bid for reelection in 2020 to Democrat Joe Biden, is the first U.S.

What is an eclipse? An eclipse occurs when one celestial body passes in front of another and obscures it. On Earth we get two kinds of eclipses. There are solar eclipses, which happen when the Moon passes in front of the Sun. There are also lunar eclipses, which happen when Earth passes between the

2024 YR4, an asteroid expected to pass close to Earth on December 22, 2032. For a brief period after its discovery, experts said there was up to a 3 percent chance that it would impact Earth on that date. Astronomers were concerned because its size—53–67 meters (174–220 feet) across—would make it a

The year was marked by historic elections and global unrest. People in more than 60 countries—representing almost 50 percent of the world’s population—went to the polls in 2024. Voters in Mexico and the United Kingdom picked new leaders, while a former U.S. president was elected to a second term in

2025 Bondi Beach shooting, mass shooting at Sydney’s Bondi Beach on December 14, 2025. Two gunmen—identified by Australian authorities as a father and son—targeted a crowd of hundreds at a gathering of Sydney’s Jewish community on the first night of Hanukkah. They killed 15 people and wounded more

Sanae Takaichi, a hardline conservative and former economic security minister, emerged victorious in the Liberal-Democratic Party’s (LDP) leadership contest on October 4, 2025. She was sworn in as Japan’s first woman prime minister on October 21. The election had been scheduled after Prime Minister

In August 2025 Myanmar’s ruling military junta—officially known as the State Administration Council (SAC)—announced plans for a multistage general election, which was held in late December 2025 and January 2026. It was the first national vote since the 2020 election, the results of which were

In October 2025 the NBA was rocked by a scandal in which active and former players and coaches, among others, were accused of participating in illegal gambling and poker schemes. Federal law enforcement announced two indictments. In one indictment, Portland Trail Blazers head coach Chauncey Billups

In September 2025 Nepal descended into political crisis after the government imposed a sweeping social media ban in an apparent attempt to silence dissent. The move, against a backdrop of economic dysfunction and widespread youth disillusionment, ignited mass protests across Kathmandu and other

Islamic State in Iraq and Syria: …shooting of 2016, and the New Orleans attack of 2025. Certain affiliates, most notably Islamic State–Khorasan Province (ISKP; also called ISIS-K) in Afghanistan and Islamic State–West Africa Province (ISWAP; also called ISIS-WA or Boko Haram) in Nigeria, are sometimes referred to as “ISIS,” despite having a separate leadership base outside…