Double Displacement Reaction Definition and Examples

A double displacement reaction is a type of reaction where two reactants exchange ions to form two new compounds. Double displacement reactions typically result in the formation of a product that is a precipitate. Double displacement reactions take the form:AB CD → AD CB Key Takeaways: Double Displacement Reaction A double displacement reaction is a type of chemical reaction in which the reactant ions exchange places to form new products.Usually, a double displacement reaction results in precipitate formation.The chemical bonds between the reactants may be either covalent or ionic.A double displacement reaction is also called a double replacement reaction, salt metathesis reaction, or double decomposition. The reaction occurs most often between ionic compounds, although technically the bonds formed between the chemical species may be either ionic or covalent in nature. Acids or bases also participate in double displacement reactions. The bonds formed in the product compounds are the same type of bonds as seen in the reactant molecules. Usually, the solvent for this type of reaction is water. Alternative Terms A double displacement reaction is also known as salt metathesis reaction, double replacement reaction, exchange, or sometimes a double decomposition reaction, although that term is used when one or more of the reactants does not dissolve in the solvent. Double Displacement Reaction Examples The reaction between silver nitrate and sodium chloride  is a double displacement reaction. The silver trades its nitrite ion for the sodiums chloride ion, causing the sodium to pick up the nitrate anion.AgNO3 NaCl → AgCl NaNO3 Heres another example: BaCl2(aq) Na2SO4(aq) → BaSO4(s) 2 NaCl(aq) How to Recognize a Double Displacement Reaction The easiest way to identify a double displacement reaction is to check to see whether or not the cations exchanged anions with each other. Another clue, if the states of matter are cited, is to look for aqueous reactants and the formation of one solid product (since the reaction typically generates a precipitate). Types of Double Displacement Reactions Double displacement reactions may be classified into several categories, including counter-ion exchange, alkylation, neutralization, acid-carbonate reactions, aqueous metathesis with precipitation (precipitation reactions), and aqueous metathesis with double decomposition (double decomposition reactions). The two types most commonly encountered in chemistry classes are precipitation reactions and neutralization reactions. A precipitation reaction occurs between two aqueous ionic compounds to form a new insoluble ionic compound. Heres an example reaction, between lead(II) nitrate and potassium iodide to form (soluble) potassium nitrate and (insoluble) lead iodide. Pb(NO3)2(aq) 2 KI(aq) → 2 KNO3(aq) PbI2(s) The lead iodide forms what is called the precipitate, while the solvent (water) and soluble reactants and products are termed the supernate or supernatant. Formation of a precipitate drives the reaction in a forward direction, as the product leaves the solution. Neutralization reactions are double displacement reactions between acids and bases. When the solvent is water, a neutralization reaction typically produces an ionic compound--a salt. This type of reaction proceeds in the forward direction if at least one of the reactants is a strong acid or a strong base. The reaction between vinegar and baking soda in the classic baking soda volcano is an example of a neutralization reaction. This particular reaction then proceeds to release a gas (carbon dioxide), which is responsible for the fizz of the reaction. The initial neutralization reaction is: NaHCO3 CH3COOH(aq) → H2CO3 NaCH3COO Youll notice the cations exchanged anions, but the way the compounds are written, its a bit trickier to notice the anion swap. The key to identifying the reaction as double displacement is to look at the atoms of the anions and compare them on both sides of the reaction. Sources Dilworth, J. R.; Hussain, W.; Hutson, A. J.; Jones, C. J.; Mcquillan, F. S. (1997). Tetrahalo Oxorhenate Anions. Inorganic Syntheses, vol. 31, pp. 257–262. doi:10.1002/9780470132623.ch42IUPAC. Compendium of Chemical Terminology (2nd ed.) (the Gold Book). (1997).March, Jerry (1985). Advanced Organic Chemistry: Reactions, Mechanisms, and Structure (3rd ed.). New York: Wiley. ISBN 0-471-85472-7.Myers, Richard (2009). The Basics of Chemistry. Greenwood Publishing Group. ISBN 978-0-313-31664-7.

The Iranian Revolution Of Iran - 1317 Words

The Iranian Revolution was at its climax in 1979 with the Revolutionary goal being met by it’s supports. Supporters of the revolution stood mixed in their goals for a new Iran. The Islamic Extremist lead by Ayatollah Khomeini wanted to install an Islamic regime inside of Iran that would follow Islamic law. Religious clerics viewed the Shah as not being a positive leader of Iran and wanted him overthrown and the country left as is. Iranians such as the middle class and students wanted to install an Islamic republic in place of the autocratic monarchical society which the Shah created. All of these groups came together to follow Ayatollah Khomeini under the presence of overthrowing the Shah. Needless to say Ayatollah Khomeini overthrow the†¦show more content†¦Change in Iran by the Shah was a part of what caused the Shah to be overthrown by the Iranians. This view is argued by Hetherington to be a minority view and not the accepted view. Fast economic or social change w as not the cause, but rather the development was too slow for the Iranians public. This is not what Persepolis says though. â€Å"The people wanted only one thing: His departure! So finally†¦Ã¢â‚¬  (Satrapi 41). The graphic novel explains the shah killed his people in the streets of their country and they wanted him to leave. In a Journal article â€Å"Industrialization and revolution in Iran: Progress or Unmet Expectation† the author explains the Shah was too slow in implementing social change and this was the downfall of his regime. It was not because the Shah’s government forced upon people more largesse that they were accustomed to that they rebelled. Rather it was a failure to meet rapidly rising expectations, rational or otherwise, a failure to deliver immediately in full measure or even in partial measure sufficient to encourage realistic hope of progress toward obtaining the material benefits of a modern industrial nation, that contributed to increasing dissatisfaction with the Shah’s government and to a climate of public opinion conducive to revolution. (Hetherington 362). The graphic novel does explain the reason why the shah was overthrown it just gives out a small explanation about him killing his own people and not what

Cebu Literature Essay Example For Students

Cebu Literature Essay Cebuano literature refers to the literary works written in Cebuano, a language widely spoken in the southern Philippines. The term is most often extended to cover the oral literary forms in both indigenous and colonial Philippines. While the majority of Cebuano writers are from the Visayas and Mindanao region, the most recognized Filipino literary outlet for them, including the Bisaya Magasin, is based in Makati city in Manila, while there is also a lively Cebuano community of writers in the language which is based outside the country. The term Cebuano literature, therefore, encompasses not only those Visayas and Mindanao-based writers writing in Cebuano, but all written output in Cebuano, wherever its source. History Cebuano literature, as much as most literature of the Philippines, started with fables and legends of the early people in the Philippines and colonial period, right down to the Mexican (Viceroyalty of New Spain) and Spanish influences. Although existence of a pre-hispanic writing system in Luzon is attested, there is proof that baybayin was widespread in the Visayas. Most of the literature produced during that period was oral. They were documented by the Spanish Jesuit Fr. Ignatio Francisco Alzinal. During the Spanish colonial period, the religious theme was predominant. Novenas and gozos, most notably the Bato Balani for the Santo Nino. The first written Cebuano literature is Maming, by Vicente Sotto, The Father of Cebuano Literature. The story was published in the first issue (July 16, 1900) of his Ang Suga. Two years later Sotto wrote, directed, and produced the first Cebuano play, Elena. It was first performed at the Teatro Junquera (in what is now Cebu City) on May 18, 1902. The play established Sottos reputation as a writer. The dedication of the play by the playwright reads, To My Motherland, that you may have remembrance of the glorious Revolution that redeemed you from enslavement. I dedicate this humble play to you. Vicente Sotto attacked the decadent forms of linambay in his newspaper Ang Suga. He was challenged by a friend to write his own play as he was always attacking the linambay form. Sotto wrote the Cebuano Ang Paghigugma sa Yutang Nataohan (Love of the Native Land) as a response. The play was successful; Sotto organized the Compania de Aficionados Filipinos. Within the year, two more plays were written by Sotto: Elena, which deals of a girls love for an insurrecto; and Aurora, which deals with a scandal involving the priests and nuns of the Colegio de la Inmaculada Concepcion. Realism in Cebuano theater was stretched too much however; even Sotto himself was a victim of the movement he started, when prior to his running for mayor in 1907, a play entitled Ang Taban (1906, by Teodulfo V. Ylaya) was released. The play dealt with a kidnap allegation involving Sotto. During the American period, Ang Suga became the medium for publication of Cebuano writers. A community of writers slowly grow, to include the names of Florentino Rallos, Filomeno Veloso, Marcial Velez, Timoteo Castro, Segundo Cinco, Vicente Ranudo, Dionisio Jakosalem, Selestino Rodriguez, Filomeno Roble, Juan Villagonzalo, Leoncio Avila and Filemon Sotto. Most of these people were recognized for their achievements by the generation right after them, as evidenced by the use of their names for major streets in Cebu City, but their role in the furtherance of Cebuano culture is lost to subsequent generations. ) Juan Villagonzalo was the first to write a Cebuano novel. Four typical novels on the love theme written by popular writers during the American period would represent the pre-war writers subconscious but collective efforts in creating a common core of meanings and values in the face of new American cultur e. These are Felicitas by Uldarico Alviola in 1912, Mahinuklugong Paglubong Kang Alicia (The Sad Burial of Alicia) by Vicente Garces in 1924, Apdo sa Kagul-anan (Bitterness of Sorrow) by Angel Enemecio in 1928-29, and Ang Tinagoan (The Secret) by Vicente Rama in 1933-34. While Felicitas and Paglubong assert the value of marital fidelity and Apdo that of feminine chastity, Tinagoan challenges the emergent value that tolerates divorce. Prostitution EssayBy the 14th century, Arab traders and their followers, venturing into the Malay Archipelago, converted some of these tribal groups into Muslims. These tribes practiced a mixture of Islam and Animism beliefs. There is also some evidence of trade among other Asian people. The Visayans were thought to have kept close diplomatic relations with Malaysia and Indonesian kingdoms since the tribal groups of Cebu were able to converse with Enrique of Malacca using the Malay language when the Portuguese explorer Ferdinand Magellan arrived in 1521. After the Magellan expedition, King Philip II of Spain sent Ruy Lopez de Villalobos and Miguel Lopez de Legazpi in 1543 and 1565 and claimed the islands for Spain. The Visayas region and many tribes began converting to Christianity and adopting western culture. By the 18th and 19th centuries, the effects of colonization on various ethnic groups soon turned sour and revolutions such as those of Francisco Dagohoy began to emerge. During the Philippine Revolution and the Philippine–American War between 1896 to 1913, the island of Negros and other neighboring islands initiated their revolution. After gaining Philippine independence from colonial rule following World War II in 1946, the Visayas region established its community and re-formed its government, producing several notable presidents coming from the Visayas region. In 2005, Palawan Island was transferred to Region VI (Western Visayas) by Executive Order 429. However this planned reorganization was held in abeyance. Hence, Palawan currently remains (as of May 2007) part of Region IV-B. Culture Legends Historical documents written in 1907 by Visayan historian Pedro Alcantara Monteclaro in his book Maragtas tell the story of the ten chiefs (Datus) who escaped from the tyranny of Datu Makatunaw from Borneo and came to the islands of Panay. The chiefs and followers were said to be the ancestors of the Visayan people. The documents were accepted by Filipino historians and found their way into the history of the Philippines. As a result, the arrival of Bornean tribal groups in the Visayas is celebrated in the festivals of the Ati-Atihan in Kalibo, Aklan and Binirayan in San Jose, Antique. Foreign historians such as William Scott conclusively proved the book to be a Visayan folk tradition. Panay boasts of the Hinilawod as its oldest and longest epic. Hypotheses A contemporary theory based on a study of genetic markers in present-day populations that Austronesian people from Taiwan populated the region of Luzon and headed south to the Visayas, Borneo, Indonesia, then to Pacific islands and to the east of the Indian Ocean. The study, though, may not explain inter-island migrations, which are also possible, such as the Tagalog migration to Luzon. According to Visayan folk traditions, the Visayas were populated by Malays migrating from Borneo to Mindanao and to the Visayas, while other Malays crossed to Palawan through Sabah. Other Malays were suggested to have crossed from Samar island to the Bicol region in Luzon. The theory suggests that those ancient tribal groups who passed through Palawan may have migrated to what is now the island of Luzon. A supplementary theory was that at that period, the Malay people were moving north from Mindanao to the Visayas and to Luzon. Various groups of Europeans and Chinese also integrated with the native population during that period.