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86-706: Vermiculite was first described in 1824 for an occurrence in Millbury, Massachusetts . Its name is from the Latin vermiculare , "to breed worms", for the manner in which it exfoliates when heated. It typically occurs as an alteration product at the contact between felsic and mafic or ultramafic rocks such as pyroxenites and dunites . It also occurs in carbonatites and metamorphosed magnesium -rich limestone . Associated mineral phases include: corundum , apatite , serpentine , and talc . It occurs interlayered with chlorite , biotite and phlogopite. Vermiculite

172-437: A soil conditioner —up to one-half the volume of the soil—is recommended. This creates air channels and allows the soil mix to breathe. Mixing vermiculite in flower and vegetable gardens or in potted plants will provide the necessary air to maintain vigorous plant growth. Where soils are sandy, mixing of vermiculite into the soil will allow the soil to hold the water and air needed for growth. Exfoliated vermiculite treated with

258-471: A female householder with no husband present, and 30.1% were non-families. Of all households, 24.6% were made up of individuals, and 10.3% had someone living alone who was 65 years of age or older. The average household size was 2.53 and the average family size was 3.03. In the town, the population was spread out, with 23.1% under the age of 18, 6.3% from 18 to 24, 31.2% from 25 to 44, 23.4% from 45 to 64, and 16.0% who were 65 years of age or older. The median age

344-436: A few hours in the sun and then place in cartons or bushel baskets and cover with vermiculite. The absorptive power of vermiculite acts as a regulator that prevents mildew and moisture fluctuation during the storage period. It will not absorb moisture from the inside of stored tubers, but it does take up free water from the outside, preventing storage rot. Where the native soil is heavy or sticky, gentle mixing of vermiculite as

430-421: A given compound may increase or decrease with temperature. The van 't Hoff equation relates the change of solubility equilibrium constant ( K sp ) to temperature change and to reaction enthalpy change. For most solids and liquids, their solubility increases with temperature because their dissolution reaction is endothermic (Δ H  > 0). In liquid water at high temperatures, (e.g. that approaching

516-432: A homogeneous mix, and its shape and surface characteristics. Exfoliated vermiculite (typically the finer grades) can be added at site to Portland cement and other aggregates, rheological aids, and water to produce roof and floor concrete screeds which are lightweight and insulating. In many cases, vermiculite-based roof screeds are used in conjunction with other insulation materials, such as polystyrene board, to form

602-447: A large increase in solubility with temperature (Δ H  > 0). Some solutes (e.g. sodium chloride in water) exhibit solubility that is fairly independent of temperature (Δ H  ≈ 0). A few, such as calcium sulfate ( gypsum ) and cerium(III) sulfate , become less soluble in water as temperature increases (Δ H  < 0). This is also the case for calcium hydroxide ( portlandite ), whose solubility at 70 °C

688-422: A lesser extent, solubility will depend on the ionic strength of solutions. The last two effects can be quantified using the equation for solubility equilibrium . For a solid that dissolves in a redox reaction, solubility is expected to depend on the potential (within the range of potentials under which the solid remains the thermodynamically stable phase). For example, solubility of gold in high-temperature water

774-505: A long time to establish (hours, days, months, or many years; depending on the nature of the solute and other factors). The rate of dissolution can be often expressed by the Noyes–Whitney equation or the Nernst and Brunner equation of the form: where: For dissolution limited by diffusion (or mass transfer if mixing is present), C s {\displaystyle C_{s}}

860-411: A minimum, which is below 120 °C for most permanent gases ), but more soluble in organic solvents (endothermic dissolution reaction related to their solvation). The chart shows solubility curves for some typical solid inorganic salts in liquid water (temperature is in degrees Celsius , i.e. kelvins minus 273.15). Many salts behave like barium nitrate and disodium hydrogen arsenate , and show

946-521: A more complex pattern is observed, as with sodium sulfate , where the less soluble deca hydrate crystal ( mirabilite ) loses water of crystallization at 32 °C to form a more soluble anhydrous phase ( thenardite ) with a smaller change in Gibbs free energy (Δ G ) in the dissolution reaction. The solubility of organic compounds nearly always increases with temperature. The technique of recrystallization , used for purification of solids, depends on

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1032-426: A percentage in this case, and the abbreviation "w/w" may be used to indicate "weight per weight". (The values in g/L and g/kg are similar for water, but that may not be the case for other solvents.) Alternatively, the solubility of a solute can be expressed in moles instead of mass. For example, if the quantity of solvent is given in kilograms , the value is the molality of the solution (mol/kg). The solubility of

1118-406: A percentage, and the abbreviation "v/v" for "volume per volume" may be used to indicate this choice. Conversion between these various ways of measuring solubility may not be trivial, since it may require knowing the density of the solution — which is often not measured, and cannot be predicted. While the total mass is conserved by dissolution, the final volume may be different from both the volume of

1204-562: A piece of smooth, low surface-energy plastic, and allowing to dry. The resulting sheet can then be peeled off the plastic. Typical end-uses for vermiculite dispersions include inclusion in high temperature coatings or binders for construction materials, gaskets, specialty papers/textiles, oxidation-resistant coating on carbon based composites, and as barrier coatings for films. The cation exchange capacity (up to 1,000 milliequivalents per kg) of vermiculite allows it to be used in fluid purification processes for waste water, chemical processing, and

1290-471: A simple ionic compound (with positive and negative ions) such as sodium chloride (common salt) is easily soluble in a highly polar solvent (with some separation of positive (δ+) and negative (δ-) charges in the covalent molecule) such as water , as thus the sea is salty as it accumulates dissolved salts since early geological ages. The solubility is favored by entropy of mixing (Δ S ) and depends on enthalpy of dissolution (Δ H ) and

1376-463: A solute's different solubilities in hot and cold solvent. A few exceptions exist, such as certain cyclodextrins . For condensed phases (solids and liquids), the pressure dependence of solubility is typically weak and usually neglected in practice. Assuming an ideal solution , the dependence can be quantified as: where the index i {\displaystyle i} iterates the components, N i {\displaystyle N_{i}}

1462-449: A solvent depends primarily on its polarity . For example, a very polar ( hydrophilic ) solute such as urea is very soluble in highly polar water, less soluble in fairly polar methanol , and practically insoluble in non-polar solvents such as benzene . In contrast, a non-polar or lipophilic solute such as naphthalene is insoluble in water, fairly soluble in methanol, and highly soluble in non-polar benzene. In even more simple terms

1548-427: A substance in a liquid may also be expressed as the quantity of solute per quantity of solution , rather than of solvent. For example, following the common practice in titration , it may be expressed as moles of solute per litre of solution (mol/L), the molarity of the latter. In more specialized contexts the solubility may be given by the mole fraction (moles of solute per total moles of solute plus solvent) or by

1634-409: A total roofing system. A bituminous binder can also be used with exfoliated vermiculite to produce a dry, lightweight roof screed which has the advantages of low thermal conductivity, low moisture content, and ease of placement (by pouring from the bag and then tamping). Exfoliated vermiculite is combined with other materials such as peat or composted pine bark to produce soilless growing medium for

1720-653: A water repellent is used to fill the pores and cavities of masonry construction and hollow blockwork to enhance fire ratings (e.g. Underwriters Laboratories Wall and Partition designs), thermal insulation , and acoustic performance. Expanded vermiculite has also been used as thermal insulation in the attics and walls of houses and in water heaters, fire safes, stoves, furnaces, and refrigerators. Exfoliated vermiculite can be combined with high alumina (also known as calcium aluminate ) cements and other aggregates such as expanded shale , clay , and slate or sodium silicate to produce refractory/insulation concretes and mortars. In

1806-632: Is a 2:1 clay , meaning it has two tetrahedral sheets for every one octahedral sheet. It is a limited-expansion clay with a medium shrink–swell capacity . Vermiculite has a high cation-exchange capacity (CEC) at 100–150 meq /100 g. Vermiculite clays are weathered micas in which the potassium ions between the molecular sheets are replaced by magnesium and iron ions. This process involves mixing exfoliated vermiculite with inorganic bonding agents such as sodium silicate , cement (specific quantities), and other compounds, such as those containing potassium, to produce an 'earth damp' mixture. This material

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1892-432: Is about half of its value at 25 °C. The dissolution of calcium hydroxide in water is also an exothermic process (Δ H  < 0). As dictated by the van 't Hoff equation and Le Chatelier's principle , lowe temperatures favorsf dissolution of Ca(OH) 2 . Portlandite solubility increases at low temperature. This temperature dependence is sometimes referred to as "retrograde" or "inverse" solubility. Occasionally,

1978-616: Is added to a calcium silicate slurry. This is then dewatered by pressing or by using one of the Fourdriner/Magnani/Hatschek processes to form a flat board which is then heat cured under pressure (typically 10–15 bar) for periods of up to 24 hours. Finer grades of exfoliated vermiculite are being used in brake linings primarily for the automotive market. The properties of vermiculite that make it an appropriate choice for use in brake linings include its thermal resistance, ease of addition to other raw materials to achieve

2064-410: Is an irreversible chemical reaction between the two substances, such as the reaction of calcium hydroxide with hydrochloric acid ; even though one might say, informally, that one "dissolved" the other. The solubility is also not the same as the rate of solution , which is how fast a solid solute dissolves in a liquid solvent. This property depends on many other variables, such as the physical form of

2150-454: Is decreasing, while Brazil's is significantly increasing. While some end processors and exfoliators of vermiculite specialize, with proprietary products sold in a wide variety of industries, some have more varied end products, with less stringent technical requirements. Some vermiculite exfoliators blend with lower-cost perlite also. Vermiculite exfoliators have an international trade association called The Vermiculite Association to represent

2236-399: Is defined for specific phases . For example, the solubility of aragonite and calcite in water are expected to differ, even though they are both polymorphs of calcium carbonate and have the same chemical formula . The solubility of one substance in another is determined by the balance of intermolecular forces between the solvent and solute, and the entropy change that accompanies

2322-667: Is equal to the solubility of the substance. When the dissolution rate of a pure substance is normalized to the surface area of the solid (which usually changes with time during the dissolution process), then it is expressed in kg/m s and referred to as "intrinsic dissolution rate". The intrinsic dissolution rate is defined by the United States Pharmacopeia . Dissolution rates vary by orders of magnitude between different systems. Typically, very low dissolution rates parallel low solubilities, and substances with high solubilities exhibit high dissolution rates, as suggested by

2408-433: Is less than 0.1 g per 100 mL of solvent. Solubility occurs under dynamic equilibrium, which means that solubility results from the simultaneous and opposing processes of dissolution and phase joining (e.g. precipitation of solids ). A stable state of the solubility equilibrium occurs when the rates of dissolution and re-joining are equal, meaning the relative amounts of dissolved and non-dissolved materials are equal. If

2494-497: Is not an instantaneous process. The rate of solubilization (in kg/s) is related to the solubility product and the surface area of the material. The speed at which a solid dissolves may depend on its crystallinity or lack thereof in the case of amorphous solids and the surface area (crystallite size) and the presence of polymorphism . Many practical systems illustrate this effect, for example in designing methods for controlled drug delivery . In some cases, solubility equilibria can take

2580-408: Is observed to be almost an order of magnitude higher (i.e. about ten times higher) when the redox potential is controlled using a highly oxidizing Fe 3 O 4 -Fe 2 O 3 redox buffer than with a moderately oxidizing Ni - NiO buffer. Solubility (metastable, at concentrations approaching saturation) also depends on the physical size of the crystal or droplet of solute (or, strictly speaking, on

2666-434: Is the mole fraction of the i {\displaystyle i} -th component in the solution, P {\displaystyle P} is the pressure, the index T {\displaystyle T} refers to constant temperature, V i , a q {\displaystyle V_{i,aq}} is the partial molar volume of the i {\displaystyle i} -th component in

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2752-421: Is the partial pressure (in atm), and c {\displaystyle c} is the concentration of the dissolved gas in the liquid (in mol/L). The solubility of gases is sometimes also quantified using Bunsen solubility coefficient . In the presence of small bubbles , the solubility of the gas does not depend on the bubble radius in any other way than through the effect of the radius on pressure (i.e.

2838-487: Is then hydraulically pressed into shape in a mold and then heat cured at temperatures up to 180 °C for up to 24 hours, depending upon the thickness of the moulded part. Such parts can withstand service temperatures of up to 1150 °C and are often used in the aluminium smelting industry as back-up insulation behind the carbon cathode in the pot cells which contain the molten mixture of cryolite and alumina. The moulded shapes and boards are used in: Exfoliated vermiculite

2924-443: Is used to germinate seeds ; very little watering is required. When vermiculite is used alone, seedlings should be fed with a weak fertilizer solution when the first true leaves appear, e.g. with one teaspoon of 5-10-5 soluble fertilizer per US gallon of water (1:768 ratio), gradually increased to one tablespoon (1:256 ratio) when transplanting. Pour vermiculite around bulbs placed in container. If clumps are dug, allow to dry for

3010-480: Is used to quantify the solubility of gases in solvents. The solubility of a gas in a solvent is directly proportional to the partial pressure of that gas above the solvent. This relationship is similar to Raoult's law and can be written as: where k H {\displaystyle k_{\rm {H}}} is a temperature-dependent constant (for example, 769.2 L · atm / mol for dioxygen (O 2 ) in water at 298 K), p {\displaystyle p}

3096-675: Is water. The town is within the Blackstone Valley and is drained by the Blackstone River . Millbury has three sites on the National Register of Historic Places : As of the census of 2020, there were 13,831 people, 4,927 households, and 3,443 families residing in the town. The population density was 812.5 inhabitants per square mile (313.7/km ). There were 5,109 housing units at an average density of 324.7 per square mile (125.4/km ). The racial makeup of

3182-651: The Town of Millbury , is a town in Worcester County , Massachusetts , United States. Located within Blackstone Valley , the population in Millbury was 13,831 at the 2020 United States Census . Millbury was first settled by Europeans in 1716. It was originally known as the Second or North Parish of Sutton . Because traveling from one part of the town to the other for meetings was time-consuming, inhabitants of

3268-412: The concentration of the solute in a saturated solution, one in which no more solute can be dissolved. At this point, the two substances are said to be at the solubility equilibrium . For some solutes and solvents, there may be no such limit, in which case the two substances are said to be " miscible in all proportions" (or just "miscible"). The solute can be a solid , a liquid , or a gas , while

3354-497: The critical temperature ), the solubility of ionic solutes tends to decrease due to the change of properties and structure of liquid water; the lower dielectric constant results in a less polar solvent and in a change of hydration energy affecting the Δ G of the dissolution reaction. Gaseous solutes exhibit more complex behavior with temperature. As the temperature is raised, gases usually become less soluble in water (exothermic dissolution reaction related to their hydration) (to

3440-485: The hydrophobic effect . The free energy of dissolution ( Gibbs energy ) depends on temperature and is given by the relationship: Δ G = Δ H – TΔ S . Smaller Δ G means greater solubility. Chemists often exploit differences in solubilities to separate and purify compounds from reaction mixtures, using the technique of liquid-liquid extraction . This applies in vast areas of chemistry from drug synthesis to spent nuclear fuel reprocessing. Dissolution

3526-427: The mass fraction at equilibrium (mass of solute per mass of solute plus solvent). Both are dimensionless numbers between 0 and 1 which may be expressed as percentages (%). For solutions of liquids or gases in liquids, the quantities of both substances may be given volume rather than mass or mole amount; such as litre of solute per litre of solvent, or litre of solute per litre of solution. The value may be given as

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3612-587: The poverty line , including 8.2% of those under age 18 and 8.4% of those age 65 or over In 1826, the first formal lyceum school was founded by Josiah Holbrook in Millbury. Public schools in Millbury fall under the jurisdiction of Millbury Public Schools school district . Approximately 2,000 students are educated in three schools: Elmwood Street School, (grades Pre-K through 2); Raymond E. Shaw Elementary School (grades 3 through 6); and Millbury Memorial Junior/Senior High School (grades 7 through 12). Millbury Public Library opened in 1864. In fiscal year 2008,

3698-412: The reagents have been dissolved in a suitable solvent. Water is by far the most common such solvent. The term "soluble" is sometimes used for materials that can form colloidal suspensions of very fine solid particles in a liquid. The quantitative solubility of such substances is generally not well-defined, however. The solubility of a specific solute in a specific solvent is generally expressed as

3784-522: The specific surface area or molar surface area of the solute). For quantification, see the equation in the article on solubility equilibrium . For highly defective crystals, solubility may increase with the increasing degree of disorder. Both of these effects occur because of the dependence of solubility constant on the Gibbs energy of the crystal. The last two effects, although often difficult to measure, are of practical importance. For example, they provide

3870-495: The Earth orbit and its rotation axis progressively change and modify the solar irradiance at the Earth surface, temperature starts to increase. When a deglaciation period is initiated, the progressive warming of the oceans releases CO 2 into the atmosphere because of its lower solubility in warmer sea water. In turn, higher levels of CO 2 in the atmosphere increase the greenhouse effect and carbon dioxide acts as an amplifier of

3956-515: The Libby area had been identified as suffering from some kind of asbestos-related abnormality. The case ended in acquittals on May 8, 2009. On June 17, 2009, the EPA issued a public health emergency in and near Libby, thereby allowing federal agencies to provide funding for health care, and for removal of contaminated insulation from affected homes. Millbury, Massachusetts Millbury , officially

4042-700: The North Parish petitioned the Massachusetts General Court to split Sutton. North Parish became Millbury on June 11, 1813, by way of an act of incorporation. Its name derived from its long history as a mill town . The Blackstone River flows through the town, and during the Industrial Revolution , provided water power to its many textile mills and factories . During this time, the inventor William Crompton worked in Millbury. Millbury's industrial history begins in

4128-468: The Noyes-Whitney equation. Solubility constants are used to describe saturated solutions of ionic compounds of relatively low solubility (see solubility equilibrium ). The solubility constant is a special case of an equilibrium constant . Since it is a product of ion concentrations in equilibrium, it is also known as the solubility product . It describes the balance between dissolved ions from

4214-490: The celebration. Later that year, a proposal for a casino was made, but the related development company pulled out when it became clear that a large majority of inhabitants were against the proposal. According to the United States Census Bureau , Millbury has a total area of 16.3 square miles (42 km ), of which 15.7 square miles (41 km ) is land and 0.5 square miles (1.3 km ), or 3.20%,

4300-791: The concentration of a saturated solution of the two. Any of the several ways of expressing concentration of solutions can be used, such as the mass , volume , or amount in moles of the solute for a specific mass, volume, or mole amount of the solvent or of the solution. In particular, chemical handbooks often express the solubility as grams of solute per 100 millilitres of solvent (g/(100 mL), often written as g/100 ml), or as grams of solute per decilitre of solvent (g/dL); or, less commonly, as grams of solute per litre of solvent (g/L). The quantity of solvent can instead be expressed in mass, as grams of solute per 100 grams of solvent (g/(100 g), often written as g/100 g), or as grams of solute per kilogram of solvent (g/kg). The number may be expressed as

4386-402: The driving force for precipitate aging (the crystal size spontaneously increasing with time). The solubility of a given solute in a given solvent is function of temperature. Depending on the change in enthalpy (Δ H ) of the dissolution reaction, i.e. , on the endothermic (Δ H  > 0) or exothermic (Δ H  < 0) character of the dissolution reaction, the solubility of

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4472-463: The early 1970s, Millbury experienced a number of large fires . The town hall burned down, followed by the Union School. A propane plant near Route 146 exploded, causing considerable damage and making nationwide news. In 2004, Millbury was designated as a Preserve America community. Millbury celebrated its bicentennial in 2013. The local Vaillancourt Folk Art designed chalkware for

4558-427: The early days of their use, these products were batched at or very close to the place of installation. This continues to be the case in some limited circumstances; however, more and more use is being made of pre-batched, proprietary mixes. Mixes containing vermiculite are used in areas where strength and corrosion/abrasion resistance are of secondary importance, the most important factor being the insulation performance of

4644-523: The early eighteenth century, not long after the area's settlement. In 1735, John Singletary began operating a mill on Singletary Brook, a stream flowing out of Singletary Lake. Around 1753, Singletary built the S & D Spinning Mill, which is still in operation, making it one of the oldest continuously operated mills in the United States . The mill is featured on the Town Seal. The mill also makes

4730-493: The extent of solubility for a given application. For example, U.S. Pharmacopoeia gives the following terms, according to the mass m sv of solvent required to dissolve one unit of mass m su of solute: (The solubilities of the examples are approximate, for water at 20–25 °C.) The thresholds to describe something as insoluble, or similar terms, may depend on the application. For example, one source states that substances are described as "insoluble" when their solubility

4816-488: The fines ($ 54.5 million) levied on them from the EPA, but the Supreme Court rejected the appeal. The United States government pursued criminal charges against several former executives and managers of the mine for allegedly disregarding and covering up health risks to employees. They were also accused of wire fraud, and of obstructing the government's cleanup efforts. As of the indictment date, about 1,200 residents of

4902-432: The general warming. A popular aphorism used for predicting solubility is " like dissolves like " also expressed in the Latin language as " Similia similibus solventur ". This statement indicates that a solute will dissolve best in a solvent that has a similar chemical structure to itself, based on favorable entropy of mixing . This view is simplistic, but it is a useful rule of thumb. The overall solvation capacity of

4988-576: The health risks associated with vermiculite and that several sites in the Salt Lake Valley had been remediated by the EPA when they were shown to be contaminated with asbestos. W. R. Grace and Company has vigorously denied these charges. The vermiculite deposit at the mine in Libby, Montana, was (and is) heavily contaminated with asbestos. Numerous people were knowingly exposed to the harmful dust of vermiculite that contained asbestos. Unfortunately,

5074-402: The in-place refractory lining . These mixes are used in industries including iron/steel, cement, and hydrocarbon processing. Vermiculite is used as an additive to fireproof wallboard . Vermiculite dispersions are typically either chemically or physically very finely delaminated vermiculite in a fluid medium. These dispersions can be used to make vermiculite 'paper' sheets by pouring them onto

5160-533: The industry's interests and to exchange information. Although not all vermiculite contains asbestos , some products were made with vermiculite that contained asbestos until the early 1990s. Vermiculite mines throughout the world are now regularly tested for it and are supposed to sell products that contain no asbestos. The former vermiculite mine in Libby, Montana , did have tremolite asbestos as well as winchite and richterite (both fibrous amphiboles )—in fact, it

5246-605: The inner parts of the Rawlings baseballs for use in Major League Baseball . In the late eighteenth and early nineteenth centuries, after learning the trade of firearms production from their father, Asa Waters and his brother, Elijah, purchased land along the Blackstone River and built mills producing goods such as guns , scythes , and sawmill equipment. In 1808, they erected an armory , which

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5332-522: The mid-1990s—and especially those known to contain the "Zonolite" brand—may contain asbestos, and therefore may be a health concern. An article published in The Salt Lake Tribune on December 3, 2006, reported that vermiculite and Zonolite had been found to contain asbestos, which had led to cancers such as those found in asbestos-related cases. The article stated that there had been a cover-up by W. R. Grace and Company and others regarding

5418-425: The mine had been operating since the 1920s, and environmental and industrial controls were virtually non-existent until the mine was purchased by the W. R. Grace and Company in 1963. Yet, knowing the human health risks, the mining company still continued to operate there until 1990. Consequently, many of the former miners and residents of Libby have been affected and continue to suffer health problems. Over 400 people in

5504-439: The particles ( atoms , molecules , or ions ) of the two substances, and of thermodynamic concepts such as enthalpy and entropy . Under certain conditions, the concentration of the solute can exceed its usual solubility limit. The result is a supersaturated solution , which is metastable and will rapidly exclude the excess solute if a suitable nucleation site appears. The concept of solubility does not apply when there

5590-492: The pollution-control of air in mines and gases in industrial processes. In addition to its ion exchange properties, exfoliated vermiculite can retain liquids within the inter-laminar voids of the individual particles, as well as between the particles themselves. In 2014, South Africa, Brazil, the US, and China were the top producers of mined, concentrated and unexfoliated vermiculite, with about 90% world share. South Africa's production

5676-416: The professional horticulturalist and for the home gardener. These mixes promote faster root growth and give quick anchorage to young roots. The mixture helps retain air, fertilizer, and moisture, releasing them as the plant requires them. These mixes were pioneered by Boodley and Sheldrake. Exfoliated vermiculite is also used as a growing medium for hydroponics . Vermiculite, alone or mixed with soil or peat,

5762-405: The salt and undissolved salt. The solubility constant is also "applicable" (i.e. useful) to precipitation , the reverse of the dissolving reaction. As with other equilibrium constants, temperature can affect the numerical value of solubility constant. While the solubility constant is not as simple as solubility, the value of this constant is generally independent of the presence of other species in

5848-414: The solubility of gas in the liquid in contact with small bubbles is increased due to pressure increase by Δ p  = 2γ/ r ; see Young–Laplace equation ). Henry's law is valid for gases that do not undergo change of chemical speciation on dissolution. Sieverts' law shows a case when this assumption does not hold. The carbon dioxide solubility in seawater is also affected by temperature, pH of

5934-483: The solubility per mole of solution is usually computed and quoted as if the solute does not dissociate or form complexes—that is, by pretending that the mole amount of solution is the sum of the mole amounts of the two substances. The extent of solubility ranges widely, from infinitely soluble (without limit, i.e. miscible ) such as ethanol in water, to essentially insoluble, such as titanium dioxide in water. A number of other descriptive terms are also used to qualify

6020-453: The solute is not recovered upon evaporation of the solvent, the process is referred to as solvolysis. The thermodynamic concept of solubility does not apply straightforwardly to solvolysis. When a solute dissolves, it may form several species in the solution. For example, an aqueous solution of cobalt(II) chloride can afford [Co(H 2 O) 6 ] , [CoCl(H 2 O) 5 ] , CoCl 2 (H 2 O) 2 , each of which interconverts. Solubility

6106-587: The solution, V i , c r {\displaystyle V_{i,cr}} is the partial molar volume of the i {\displaystyle i} -th component in the dissolving solid, and R {\displaystyle R} is the universal gas constant . The pressure dependence of solubility does occasionally have practical significance. For example, precipitation fouling of oil fields and wells by calcium sulfate (which decreases its solubility with decreasing pressure) can result in decreased productivity with time. Henry's law

6192-573: The solution, and by the carbonate buffer. The decrease of solubility of carbon dioxide in seawater when temperature increases is also an important retroaction factor (positive feedback) exacerbating past and future climate changes as observed in ice cores from the Vostok site in Antarctica . At the geological time scale, because of the Milankovich cycles , when the astronomical parameters of

6278-409: The solvation. Factors such as temperature and pressure will alter this balance, thus changing the solubility. Solubility may also strongly depend on the presence of other species dissolved in the solvent, for example, complex-forming anions ( ligands ) in liquids. Solubility will also depend on the excess or deficiency of a common ion in the solution , a phenomenon known as the common-ion effect . To

6364-415: The solvent and the sum of the two volumes. Moreover, many solids (such as acids and salts ) will dissociate in non-trivial ways when dissolved; conversely, the solvent may form coordination complexes with the molecules or ions of the solute. In those cases, the sum of the moles of molecules of solute and solvent is not really the total moles of independent particles solution. To sidestep that problem,

6450-441: The solvent is removed, all of the substance that had dissolved is recovered. The term solubility is also used in some fields where the solute is altered by solvolysis . For example, many metals and their oxides are said to be "soluble in hydrochloric acid", although in fact the aqueous acid irreversibly degrades the solid to give soluble products. Most ionic solids dissociate when dissolved in polar solvents. In those cases where

6536-532: The solvent is usually solid or liquid. Both may be pure substances, or may themselves be solutions. Gases are always miscible in all proportions, except in very extreme situations, and a solid or liquid can be "dissolved" in a gas only by passing into the gaseous state first. The solubility mainly depends on the composition of solute and solvent (including their pH and the presence of other dissolved substances) as well as on temperature and pressure. The dependency can often be explained in terms of interactions between

6622-660: The town during his youth. He visited his aunt, Delia C. Torrey, during his presidency to celebrate Millbury's centennial . The Torrey House, where President Taft stayed, is now commonly called the Taft House. In 1824, the mineral called Vermiculite was first found in Millbury. Due to the Flood Control Act of 1944 , the Worcester Flood Diversion Channel was constructed in that year within Millbury, as well as nearby Auburn . In

6708-417: The town have died from asbestos-related disease due to contamination from vermiculite mining from nearby Zonolite Mountain, where soil samples were found to be loaded with fibrous tremolite (known to be a very hazardous form of asbestos), and countless others there who insulated their homes with Zonolite have succumbed to asbestos-related diseases, most of whom never were employed in environments where asbestos

6794-406: The town spent 1.15% ($ 358,097) of its budget on the library. Soluble In chemistry , solubility is the ability of a substance , the solute , to form a solution with another substance, the solvent . Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solubility of a substance in a specific solvent is generally measured as

6880-402: The town was 97.19% White , 0.53% African American , 0.15% Native American , 1.02% Asian , 0.03% Pacific Islander , 0.23% from other races , and 0.84% from two or more races. Hispanic or Latino of any race were 1.02% of the population. There were 4,927 households, out of which 30.2% had children under the age of 18 living with them, 55.7% were married couples living together, 10.9% had

6966-458: The two substances and the manner and intensity of mixing. The concept and measure of solubility are extremely important in many sciences besides chemistry, such as geology , biology , physics , and oceanography , as well as in engineering , medicine , agriculture , and even in non-technical activities like painting , cleaning , cooking , and brewing . Most chemical reactions of scientific, industrial, or practical interest only happen after

7052-570: The vermiculite was sold under the commercial name Zonolite. The Zonolite brand and the mine were acquired by the W. R. Grace and Company in 1963. Mining operations at the Libby site stopped in 1990 in response to asbestos contamination. While in operation, the Libby mine may have produced 80% of the world's supply of vermiculite. The United States government estimates that vermiculite was used in more than 35 million homes, but does not recommend its removal. Nevertheless, homes or structures containing vermiculite or vermiculite insulation dating from before

7138-406: Was 39 years. For every 100 females, there were 93.3 males. For every 100 females age 18 and over, there were 88.4 males. The median income for a household in the town was $ 51,415, and the median income for a family was $ 62,564. Males had a median income of $ 41,912 versus $ 28,973 for females. The per capita income for the town was $ 23,531. About 4.1% of families and 6.3% of the population were below

7224-481: Was an issue. After a 1999 Seattle Post-Intelligencer story claimed that asbestos-related disease was common in the town, the EPA, in response to political pressure, made cleanup of the site a priority and called Libby the worst case of community-wide exposure to a toxic substance in U.S. history. The EPA has spent $ 120 million in Superfund money on cleanup. In October 2006, W. R. Grace and Company tried to appeal

7310-471: Was formed underground through essentially the same geologic processes as the contaminants. Pure vermiculite does not contain asbestos and is non-toxic. Impure vermiculite may contain, apart from asbestos, also minor diopside or remnants of the precursor minerals biotite or phlogopite . The largest and oldest vermiculite mine in the United States was started in the 1920s, at Libby, Montana , and

7396-598: Was successful until forced to close suddenly in 1841. It reopened at the start of the American Civil War in 1861. With the wealth received from the industry, Asa began construction of the Asa Waters Mansion in 1826. Designed by local architect Asher Benjamin , it was completed six years later. Louise Taft , mother of United States President William Howard Taft , resided in Millbury for many years, and President Taft spent many summer vacations in

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