Oxides can be named after the amount of oxygen atoms in the oxide. Oxides containing only one oxygen are called oxide or monoxide, those containing two oxygen atoms dioxide, three trioxide, four tetroxide, and so on following the Greek numerical prefixes. There are two other types of oxide—peroxide and superoxide. Both count as oxides but have different oxidation states and react in different ways compared to oxides. ...

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Oxide, Oxide - Current naming, Oxide - Chemical properties, Oxide - Types of oxides, Oxide - Common oxides sorted by oxidation state

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The earliest settlement phase known at et-Tell, called "Pre-Urban", coincides with the Early Bronze Age I and lasted from about 3200 BC to 3100 BC. In this period, an unfortified village (about 200 m in diameter, large for the EBI) was settled at the site, with accompanying tombs dug in caves on the northeastern slopes of the hill. Pottery styles from this period show both indigenous and foreign cultural influences and may signify a mingling of peoples from nearby areas and newcomers emigrating from more distant regions. Over time, the foreign element ...

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Et-Tell, Et-Tell - Location and identification, Et-Tell - Excavation history, Et-Tell - Settlement phases, Et-Tell - Comparisons with the Biblical account, Et-Tell - External references

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When breathed in, lead tetroxide irritates lungs. In case of high dose, the victim feels metallic taste in mouth, chest pain, and abdominal pain. When ingested, it gets dissolved in the gastric acid and gets absorbed, leading to lead poisoning. High concentrations can be absorbed through skin as well; therefore it is important to keep the safety precautions when working with lead-based paint. Long-term contact with lead tetroxide may lead to accumulation of lead compounds in organism, with development of symptoms of acute lead poisoning. Chronic poisoning displays as agitation, irritability, vision disorders, hype ...

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Red lead, Red lead - Preparation, Red lead - Chemical properties, Red lead - Use, Red lead - Physiological effects, Red lead - Ecological issues, Red lead - Historic note

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Oxides of more electropositive elements tend to be basic. They are called basic anhydrides; adding water, they may form basic hydroxides. For example, sodium oxide is basic; when hydrated, it forms sodium hydroxide. Oxides of more electronegative elements tend to be acids. They are called acid anhydrides; adding water, they may form oxygen acids. For example, dichlorine heptoxide is acid; perchloric acid is a more hydrated form. Some oxides can act as both acid and base, at different times. They are amphoteric. An example is aluminium oxide. Some oxides do ...

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Oxide, Oxide - Current naming, Oxide - Chemical properties, Oxide - Types of oxides, Oxide - Common oxides sorted by oxidation state

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With iron oxides and with elementary iron, lead tetroxide forms insoluble iron(II) and iron(III) plumbates, which is the basis of the anti-corrosive properties of lead-based paints applied to iron objects. When heated to 500 °C, it decomposes to lead(II) oxide and oxygen. At 580 °C, the reaction is complete. 2 Pb3O4 → 6 PbO + O2 Nitric acid dissolves the lead(II) oxide component, leaving behind the insoluble lead(IV) oxide: Pb3O4 + 4 HNO3 → PbO2 + 2 Pb(NOSee also:

Red lead, Red lead - Preparation, Red lead - Chemical properties, Red lead - Use, Red lead - Physiological effects, Red lead - Ecological issues, Red lead - Historic note

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Oxides are formed in redox reactions through oxidation in which a reducing agent is allowed to react with molecular oxygen (O2) or oxidizing agents which contain oxygen, such as hydrogen peroxide (H2O2) and permanganate (MnO4-). Oxides are characterized by a redistribution of electrons, in which the oxygen atoms have a net surplus of electrons and the other atoms a net lack. In oxides of hydrogen, carbon, nitrogen, sulfur, phosphorus and halogens, covalent bonds occur between oxygen and ...

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Oxide, Oxide - Current naming, Oxide - Chemical properties, Oxide - Types of oxides, Oxide - Common oxides sorted by oxidation state

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Jabir Ibn Hayyan was born around 721 in the town of Tus in Khorasan, Persia (present-day Iran). His father, a druggist of the Azd tribe, was executed for conspiring to overthrow the Umayyad caliphate. As a young man Jabir was sent to Kufa (present Iraq), to study the Qu'ran and mathematics. In Kufa he became a student of the celebrated Islamic teacher and sixth Imam Ja'far al-Sadiq. He lived for most of his ...

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Geber, Geber - Biography, Geber - Contributions to chemistry, Geber - Contributions to alchemy, Geber - Writings by Jabir, Geber - Translated work of Jabir

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The writings of Jabir Ibn Hayyan can be divided into four categories: 1. The 112 Books dedicated to the Barmakids, viziers of Caliph Harun al-Rashid who were descended from Zoroastrian priests from Bactria. This group includes the Arabic version of the Emerald Tablet, an ancient work that is the foundation of the Hermetic or "spiritual" alchemy. In the Middle Ages it was translated into Latin (Tabula Smaragdina) and ...

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Geber, Geber - Biography, Geber - Contributions to chemistry, Geber - Contributions to alchemy, Geber - Writings by Jabir, Geber - Translated work of Jabir

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Jabir became an alchemist at the court of Caliph Harun al-Rashid, for whom he wrote the Kitab al-Zuhra ("The Book of Venus", on "the noble art of alchemy"). Jabir's alchemical investigations revolved around the ultimate goal of takwin — the artificial creation of life. Alchemy had a long relationship with Shi'ite mysticism; according to the first Imam, Ali ibn Abi Talib, "alchemy is the sister of prophecy". Jabir's interest in alchemy was probably inspired by his teacher Ja'far al-Sadiq, and he was himself called "the Sufi", indicating that he fo ...

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Geber, Geber - Biography, Geber - Contributions to chemistry, Geber - Contributions to alchemy, Geber - Writings by Jabir, Geber - Translated work of Jabir

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The site of et-Tell (Arabic for "the ruin-heap") is about 3 km east of the modern village of Beitin (Bethel), atop a watershed plateau overlooking the Jordan Valley and the city of Jericho 14 km east. Edward Robinson suggested in 1838 that et-Tell could be the location of the Biblical city of Ai, as did Charles Wilson in 1866, on the evidence of Biblical references and nearby topography. This identification was backed by the American scholar William Foxwell Albright, who further argued in a 1924 paper that the site of et-Tell held the ...

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Et-Tell, Et-Tell - Location and identification, Et-Tell - Excavation history, Et-Tell - Settlement phases, Et-Tell - Comparisons with the Biblical account, Et-Tell - External references

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The first archaeological exploration of et-Tell was undertaken in September 1928 under the supervision of John Garstang. Eight trenches were dug, five against the outer side of the southern city wall and three within the city itself. The outcome of this excavation was never formally published, and the only report known is a three-page summary filed by Garstang at the end of the work. In a later book, Garstang claimed that Late Bronze Age pottery, dating to ca. 1400 BC, was found in this excavation, but this pottery was not mentioned in his earlier ...

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Et-Tell, Et-Tell - Location and identification, Et-Tell - Excavation history, Et-Tell - Settlement phases, Et-Tell - Comparisons with the Biblical account, Et-Tell - External references

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Gypsum occurs in nature as flattened and often twinned crystals and transparent cleavable masses called selenite. It may also occur silky and fibrous, in which case it is commonly called satin spar. Finally it may also be granular or quite compact. In hand-sized samples, it can be anywhere from transparent to opaque. A very fine-grained white or lightly-tinted variety of gypsum is called alabaster, which is prized for ornamental work of various sorts. In arid areas, gypsum can occur in a flower-like form typically opaque with emb ...

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Gypsum, Gypsum - Chemical structure, Gypsum - Occurrence, Gypsum - Uses, Gypsum - External link, Gypsum - Place names

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If et-Tell is indeed Ai, this poses a problem for defenders of the literal historicity of the Biblical accounts concerning the origin of ancient Israel. The reason for this is that traditional dating schemes place the Exodus from Egypt and Joshua's conquest around 1400 BC. In this version of events, Joshua and the invading Israelites are depicted as conquering Ai, killing its residents and burning the city; however, et-Tell was unoccupied at this time according to the established archaeological chronology, and the later Iron Age I village ap ...

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Et-Tell, Et-Tell - Location and identification, Et-Tell - Excavation history, Et-Tell - Settlement phases, Et-Tell - Comparisons with the Biblical account, Et-Tell - External references

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Gypsum is also the name of several towns in the United States of America: Gypsum, Kansas Gypsum, Ohio Gypsum, Colorado ...

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Gypsum, Gypsum - Chemical structure, Gypsum - Occurrence, Gypsum - Uses, Gypsum - External link, Gypsum - Place names

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