Iodine trichloride is a chemical compound. Its chemical formula is ICl. It has iodine and chloride ions in it. The iodine is in the +3 oxidation state.
Iodine trichloride is a yellow solid. It melts at . It conducts electricity when it melts. It is a strong oxidizing agent. It is an interhalogen.
It is made by reacting a lot of cold iodine with liquid chlorine. It can also be made by heating liquid iodine with chlorine gas at .
Silver iodate
Silver iodate is a chemical compound. Its chemical formula is AgIO. It has silver and iodate ions in it. The silver is in the +1 oxidation state.
Silver iodate is a colorless solid. It does not dissolve in water. It is an oxidizing agent.
It is made by reacting silver nitrate with sodium iodate.
SemEval
SemEval (Semantic Evaluation) is a series of workshops that focus on evaluating computer systems that interpret the meaning of human language (aka Computational Semantic systems).
Iodate
Iodate is an ion. Its chemical formula is IO. The iodine is in the +5 oxidation state. It can be made by reduction of periodate. They are similar to chlorates. They react with acids to make iodic acid. They are salts of iodic acid. An example would be sodium iodate.
Iodine pentafluoride
Iodine pentafluoride is a chemical compound. Its chemical formula is IF. It has iodine and fluoride ions. The iodine is in its +5 oxidation state.
Iodine pentafluoride is a pale yellow liquid. It is an interhalogen. It is also a powerful oxidizing agent. It reacts with water to make hydrofluoric acid.
Iodine pentafluoride is made by burning iodine in fluorine gas.
It is used in organic chemistry (amine to nitrile conversion after hydrolysis).
Iodine pentoxide
Iodine pentoxide, also known as iodine(V) oxide and diiodine pentoxide is a chemical compound. Its chemical formula is IO. It has iodine and oxide ions. The iodine is in its +5 oxidation state.
Iodine pentoxide is a white solid. It breaks down to iodine and oxygen when heated. It reacts with carbon monoxide to make carbon dioxide and iodine. It is a strong oxidizing agent. It reacts with water to make iodic acid.
Iodine pentoxide is made by heating iodic acid to in dry air.
It is used to see how much carbon monoxide is in a sample of gas.
Potassium iodate
Potassium iodate is a chemical compound. Its chemical formula is KIO. It has potassium and iodate ions in it.
Potassium iodate is a white solid. It is a strong oxidizing agent. It is similar to potassium bromate and potassium chlorate. It reacts violently with many reducing agents.
Potassium iodate is made by reacting iodic acid with potassium hydroxide or by reacting iodine with potassium hydroxide. This second reaction makes the iodide and the iodate.
Potassium iodate is used to add iodine to salt. It is better than potassium iodide because it does not oxidize to iodine and evaporate like potassium iodide does. It is sometimes used in flour just like potassium bromate.
It is also used for radiation protection. A nuclear explosion can make radioactive iodine, which goes into the thyroid and can make cancer. Eating potassium iodate makes the thyroid full of nonradioactive iodine and prevents radioactive iodine from going in. It lasts longer than potassium iodide.
Sodium iodate
Sodium iodate is a chemical compound. Its chemical formula is NaIO. It has sodium and iodate ions in it.
Sodium iodate is a colorless solid. It is similar to sodium chlorate. It is a strong oxidizing agent. It reacts with sodium hypochlorite to make sodium periodate. It can catch things on fire.
It is made by dissolving iodic acid or iodine in sodium hydroxide solution. Iodine dissolving also makes sodium iodide.
It is used to make sodium periodate.
Tuff
Tuff (from Italian "tufo") is a type of rock produced by the eruption of volcanoes.
It consists of consolidated volcanic ash ejected from vents during a volcanic eruption. Rock with more than 50% tuff is called "tuffaceous". The chemical and mineral composition of tuff varies according to what was in the molten magma.
In a volcanic eruption, Magma is blown apart by volcanic gases and steam. The products are volcanic gases, lava, steam, and tephra (fragments). The solid material produced and thrown into the air is called "tephra", regardless of composition or fragment size. If the pieces of ejecta are small, the material is called volcanic ash, defined as such particles less than 2 mm in diameter, sand-sized or smaller. These particles are small, slaggy pieces of magma and rock that have been tossed into the air by outbursts of steam and other gases.
Among the loose beds of ash that cover the slopes of many volcanoes, three classes of materials are represented.
In some great volcanic explosions nothing but materials of the second kind were emitted, as at Mount Bandai in Japan in 1888. There have also been many eruptions in which the quantity of broken sedimentary rocks that mingled with the ash is very great.
These materials, in contrast to true ashes, tend to occur in "angular fragments". When they form a large part of the mass the rock is more properly a 'volcanic breccia' than a tuff. A breccia is a rock with sharp-edged fragments in it.
The ashes vary in size from large blocks twenty feet or more in diameter to the minutest impalpable dust. The large masses are called 'volcanic bombs'; they have mostly a rounded, elliptical or pear-shaped form owing to rotation in the air before they solidified. Many of them have ribbed or nodular surfaces, and sometimes they have a crust intersected by many cracks like the surface of a loaf of bread. Any ash in which they are very abundant is called an agglomerate.
A tuff of recent origin is generally loose, but the older tuffs have usually been cemented together by pressure and the action of infiltrating water. This makes rocks which, while not very hard, are strong enough to be used for building purposes (e.g. in the neighborhood of Rome).
Many volcanoes stand near the sea, and the ashes cast out by them are mingled with the sediments that are gathering at the bottom of the waters. In this way ashy muds or sands or even in some cases ashy limestones are formed. As a matter of fact most of the tuffs found in the older rock formations contain mixtures of clay, sand, and sometimes fossil shells, which prove that they were beds spread out under water.
During some volcanic eruptions a layer of ashes several feet in thickness is deposited over a considerable district, but such beds thin out rapidly as the distance from the crater increases, and ash deposits covering many square miles are usually very thin.
The showers of ashes often follow one another after longer or shorter intervals, and hence thick masses of tuff, whether of subaerial or of marine origin, have mostly a stratified character. In the fine beds it is often developed in great perfection.
Welded tuff is a pyroclastic flow of lava which was hot enough to weld together. During welding, the glass shards and pumice fragments adhere together (necking at point contacts), deform, and compact together.
A hot lava flow welded by heat can be highly voluminous, such as the Lava Creek Tuff erupted from Yellowstone Caldera in Wyoming 640,000 years ago. Lava Creek Tuff was at least 1000 times as large as the deposits of the May 18, 1980 eruption of Mount St. Helens. It had a Volcanic Explosivity Index (VEI) of 8—greater than any eruption known in the last 10,000 years.
Basaltic tuffs are occur widely. They are found in Skye, Mull, Antrim and other places, where there are tertiary volcanic rocks; in Scotland, Derbyshire and Ireland among the carboniferous strata; and among the still older rocks of the Lake District, southern uplands of Scotland and Wales.