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74-504: The original house was built about 1766, and is a 2 + 1 ⁄ 2 -story, stuccoed stone structure. It has a rear wing. It was listed on the National Register of Historic Places in 1972. The homes of David Havard and two of his brothers were used as lodging and headquarters by officers serving under George Washington , during the encampment of Washington's army at Valley Forge from December 1777 through June 1778. Upon

148-498: A coating for the outside of a building and " plaster " to a coating for interiors. As described below, however, the materials themselves often have little or no difference. Other European languages, notably Italian, do not have the same distinction: stucco means plaster in Italian and serves for both. The basic composition of stucco is lime , water, and sand. The difference in nomenclature between stucco, plaster , and mortar

222-399: A finish layer, which is thinner and faster to apply, compared to the traditional application of three-coat stucco. Imitation stone stucco can also be produced using the traditional application, but with marble dust being added to the mixture. As with any cement-based material, stucco must be reinforced to resist movement cracking. Plastic or wire mesh lath , attached with nails or screws to

296-421: 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

370-447: 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

444-422: 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

518-505: 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}}

592-411: 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

666-521: 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

740-426: 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

814-406: 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

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888-433: A sand finish or sprayed. Originally, the lath material was strips of wood installed horizontally on the wall, with spaces between, that would support the wet plaster until it cured. This lath and plaster technique became widely used. In exterior wall applications, the lath is installed over a weather-resistant asphalt - impregnated felt or paper sheet that protects the framing from the moisture that can pass through

962-471: 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

1036-402: A solid masonry , brick , or stone surface. The finish coat usually contained an integral color and was typically textured for appearance. Then with the introduction and development of heavy timber and light wood-framed construction methods, stucco was adapted for this new use by adding a reinforcement lattice, or lath , attached to and spanning between the structural supports and by increasing

1110-463: 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}}

1184-449: 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

1258-427: 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

1332-422: A warmer climate (like California , Nevada , Arizona , New Mexico and Florida ), stucco is the predominant exterior for both residential and commercial construction. Stucco exterior (with wood frame interior) became a popular alternative in the southwestern United States during the 1970s, as the masonry labor costs for adobe rose. Stucco has also been used as a sculptural and artistic material. Stucco relief

1406-400: A weaker and brittler stucco. Solubility 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 the concentration of

1480-432: 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,

1554-410: 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

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1628-419: Is based more on use than composition. Until the latter part of the nineteenth century, it was common that mortar as well as plaster , which was used inside a building, and stucco, which was used outside, would consist of the same primary materials: lime and sand . Animal or plant fibers were often added for additional strength. Sometimes additives such as acrylics and glass fibers are added to improve

1702-399: 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

1776-667: 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

1850-433: 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

1924-497: 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

1998-408: 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

2072-434: 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

2146-421: 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.

2220-480: 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}

2294-520: 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

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2368-436: Is very hard and brittle and can easily crack and separate from the surcface if the base on which it is applied is not stable. Typically its color was gray, from the innate color of most Portland cement, but white Portland cement is also available. Today's stucco manufacturers offer a very wide range of colors that can be mixed integrally in the finish coat. Other materials such as stone and glass chips are sometimes "dashed" onto

2442-549: Is visually extended into a heavenly architecture with a depiction of Christ , the Virgin Mary or the Last Judgment at the center. Stucco is used to form a semi-plastic extension of the real architecture that merges into the painted architecture. Because of its " aristocratic " appearance, Baroque-looking stucco decoration was used frequently in upper-class apartments of the 19th and early 20th century. Beginning in

2516-440: The arabesque reached its full maturity, carved stucco remained a very common medium for decoration and calligraphic inscriptions. Indian architecture used stucco as a material for sculpture in an architectural context. It is rare in the countryside. In Roman art of the late Republic and early Empire, stucco was used extensively for the decoration of vaults. Though marble was the preferred sculptural medium in most regards, stucco

2590-497: 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

2664-485: 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

2738-427: 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

2812-412: 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

2886-522: 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

2960-444: The 1920s, stucco, especially in its Neo-Renaissance and Neo-Baroque materialization, became increasingly unpopular with modern architects in some countries, resulting not only in new buildings without stucco but also in a widespread Movement  [ de ] to remove the stucco from existing tenements. Stucco was still employed in the 1950s in molded forms for decorating the joints between walls and ceilings inside houses. It

3034-473: The Baroque concept that integrates the three classic arts , architecture , sculpture , and painting . The Greco-Buddhist art of modern Afghanistan and northern Pakistan made extensive use in monasteries and temples of stucco for three-dimensional monumental sculpture as well as reliefs. These were usually carved from a rough modelling over a framework and then painted. Similar techniques are used for

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3108-787: The David Havard House on May 21, 1778, and shortly afterward, the Bradfords moved elsewhere. Several generations of the Havard family occupied the house until it was purchased in 1881 by Alexander Cassatt , president of the Pennsylvania Railroad , who turned the surrounding farmland into a 600-acre hunting preserve called Chesterbrook Farm, known for its racing stables. The house, which still stands on Bradford Road in Chesterbrook, Pennsylvania, remains in use as

3182-495: 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

3256-468: 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

3330-875: The arrival of the Continental Army at Valley Forge, the David Havard House served as quarters for Colonel William Bradford and Colonel Elias Boudinot , who were brothers-in-law. Bradford's older brother Thomas, a captain, arrived in January 1778, and their father, Colonel William Bradford Sr. , joined them in April 1778. General Charles Lee , who had been held prisoner by the British in New York, first arrived in Valley Forge in April 1778, after Boudinot negotiated an exchange of prisoners. He took up residence in

3404-420: The building as well as in the wall by its excellent permeability- It is more elastic and workable than cement render. Lime itself is usually white; color comes from the aggregate or any added pigments . Lime stucco has the property of being self-healing to a limited degree because of the slight water solubility of lime (which in solution can be deposited in cracks, where it solidifies). Portland cement stucco

3478-655: The clubhouse for the Picket Post Swim and Tennis Club. Stucco Stucco or render is a construction material made of aggregates , a binder , and water. Stucco is applied wet and hardens to a very dense solid. It is used as a decorative coating for walls and ceilings, exterior walls, and as a sculptural and artistic material in architecture. Stucco can be applied on construction materials such as metal , expanded metal lath , concrete , cinder block , or clay brick and adobe for decorative and structural purposes. In English, "stucco" sometimes refers to

3552-791: 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

3626-402: 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

3700-493: 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

3774-458: The finish coat before drying, with the finished product commonly known as "rock dash", "pebble dash", or also as roughcast if the stones are incorporated directly into the stucco, used mainly from the early 20th through the early 21st centuries. As a building material, stucco is a durable, attractive, and weather-resistant wall covering. It was traditionally used as both an interior and exterior finish applied in one or two thin layers directly over

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3848-483: 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

3922-472: The life-size statues decorating the gopurams of Hindu temples in modern South Asia . Since stucco can be used for decoration as well as for figurative representation, it provides an ideal transitive link from architectural details to wall paintings such as the typically Baroque trompe-l'œil ceilings, as in the work of the Wessobrunner School . Here, the real architecture of the church

3996-439: 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

4070-429: The plaster something to attach to and to add strength. Types include expanded-metal lath, woven-wire lath, and welded-wire lath. If applied during very dry weather, the layers of stucco are sprayed with water for one or more days to keep a level of moisture within the stucco while it cures, a process known as "moist curing". If the stucco dries too soon, the chemical hardening ("hydration") will be incomplete, resulting in

4144-472: The porous stucco. Following World War II , the introduction of metal wire mesh , or netting, replaced the use of wood lath. Galvanizing the wire made it corrosion resistant and suitable for exterior wall applications. At the beginning of the 21st century, this "traditional" method of wire mesh lath and three coats of exterior plaster was still widely used. In some parts of the United States with

4218-405: 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

4292-414: 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

4366-483: 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

4440-401: 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 the solvent

4514-453: 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

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4588-587: 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

4662-573: 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

4736-409: 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

4810-415: 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,

4884-441: 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

4958-486: The structural framing, is embedded into the base coat to provide stiffening for the stucco. Where stucco is to be applied to a structure of wood-framing or light-gauge steel framing, the framing is protected from moisture damage by applying a cement based primer, or a vapor-permeable, water-resistant weather barrier; typically an asphalt -saturated paper or one of a variety of manufactured plastic-based sheets, known as " building wraps " or "stucco wraps". The properties of

5032-487: The structural properties of the stucco. This is usually done with what is considered a one-coat stucco system, as opposed to the traditional three-coat method. In the latter nineteenth century, Portland cement was added with increasing frequency to cover surfaces in contact with soil or water. At the same time, traditional lime plasters were often being replaced by gypsum plaster. Lime is almost as good in balancing humidity as clay. It prevents moisture accumulation inside

5106-493: The thickness and number of layers of the total system. The lath added support for the wet plaster and tensile strength to the brittle, cured stucco; while the increased thickness and number of layers helped control cracking. The traditional application of stucco and lath occurs in three coats—the scratch coat, the brown coat and the finish coat. The two base coats of plaster are either hand-applied or machine sprayed. The finish coat can be troweled smooth, hand-textured, floated to

5180-458: 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

5254-404: The weather barrier must not only protect the framing from rain and moisture, but at the same time allow the free passage of any water vapor generated inside the building to escape through the wall. A wide variety of stucco accessories, such as weep screeds , control and expansion joints, corner-aids and architectural reveals are sometimes also incorporated into the lath. Wire lath is used to give

5328-422: Was better for use in vaults because it was lighter and better suited to adapt to the curvature of the ceiling. Baroque and Rococo architecture makes heavy use of stucco. Examples can be found in churches and palaces, where stucco is mostly used to provide a smooth, decorative transition from walls to ceiling, decorating and giving measure to ceiling surfaces. Stucco is an integral part of the art of belcomposto ,

5402-453: Was generally painted the same colour as the ceiling and used in designs where a picture rail or rat rail was in use. Modern stucco is used as an exterior cement plaster wall covering. It is usually a mix of sand , Portland cement , lime and water, but may also consist of a proprietary mix of additives including fibers and synthetic acrylics that add strength and flexibility. Modern synthetic stucco can be applied as one base layer and

5476-479: Was used in the architectural decoration schemes of many ancient cultures. Examples of Egyptian , Minoan , and Etruscan stucco reliefs remain extant. In the art of Mesopotamia and ancient Persian art there was a widespread tradition of figurative and ornamental internal stucco reliefs, which continued into Islamic art , for example in Abbasid Samarra , now using geometrical and plant-based ornament. As

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