Calcium hydroxide Ca

Some carbonates are important industrial chemicals. Calcium carbonate occurs naturally in several forms, including limestone, and is used in the production of quicklime, calcium oxide CaO, slaked (or hydrated) lime, calcium hydroxide Ca(OH)2 and cement. 

Hydrogen sulfide, H2S, is removed by a variety of processes, of which one is a regenerative solution process using aqueous solutions of sodium hydroxide, NaOH, calcium hydroxide, Ca(OH)2, sodium phosphate, Na PO, and sodium carbonate, Na2C02. 

Calcium hydroxide (Ca(OH)2 (slaked lime) ) White powder soluble in water yielding lime water. Alkaline... 

The chemical formula for limestone is CaCOj and upon burning forms calcium oxide (CaO), which is known as burnt lime. Calcium oxide, when mixed with water, forms calcium hydroxide (Ca(OH)2). Calcium hydroxide is used to treat water as a coagulation aid along with aluminum sulfate. 

In this reaction, the nickel ions of the nickel sulfate (NiSO ) are exchanged for the calcium ions of the calcium hydroxide [Ca(OH)2 ] molecule. Similarly, a resin with hydrogen ions available for exchange will exchange those ions for nickel ions from solution. The reaction can be written as follows ... 

Neutralizers. To maintain pH levels in alkaline regions, it is necessary to neutralize the acidic components of the corrosive medium. Water-soluble, alkaline materials, such as sodium hydroxide (NaOH), ammonium hydroxide (NH OH) and calcium hydroxide [Ca(OH)J, can be used to obtain pH levels around 9.6. However, care must be taken to avoid reaching pH levels that are... 

Hydrogen Sulfide Scavengers. Hydrogen sulfide (H S) can be neutralized by using sodium hydroxide (NaOH) and calcium hydroxide [Ca(OH)j] [213,214]. The reaction is... 

For the corrosion process to proceed, the corrosion cell must contain an anode, a cathode, an electrolyte and an electronic conductor. When a properly prepared and conditioned mud is used, it causes preferential oil wetting on the metal. As the metal is completely enveloped and wet by an oil environment that is electrically nonconductive, corrosion does not occur. This is because the electric circuit of the corrosion cell is interrupted by the absence of an electrolyte. Excess calcium hydroxide [Ca(OH)j] is added as it reacts with hydrogen sulfide and carbon dioxide if they are present. The protective layer of oil film on the metal is not readily removed by the oil-wet solids as the fluid circulates through the hole. 

Uchino and Azuma [498] proposed a way in which to recycle the filtrate solutions. The process consists of adding calcium hydroxide, Ca(OH)2, to the filtrate, yielding a calcium fluoride, CaF2 precipitate and gaseous ammonia, NH3. The fluorine and ammonia are recovered in forms that are suitable for reutilization. 

Hydrogen for weather balloons is often supplied by the reaction between solid calcium hydride, CaH2, and water to form solid calcium hydroxide, Ca(OH)2, and hydrogen gas, H ... 

FIGURE 14.21 Calcium reacts gently with cold water to produce hydrogen and calcium hydroxide, Ca(OH)2. 

C16-0106. Write the equilibrium reaction and equilibrium constant expression for each of the following processes (a) Trichloroacetic acid, CI3 CCO2H, is added to water, (b) Aniline, (Cg H5) NH2, a weak base, is dissolved in water, (c) Solid calcium hydroxide, Ca (OH)2, a sparingly soluble salt, is added to water. 

Sodium hydroxide (NaOH) (caustic soda) Potassium hydroxide (KOH) (caustic potash) Calcium hydroxide (Ca(OH)2) (slaked lime) Ammonium hydroxide (NH4OH) (aqueous ammonia solution) White deliquescent solid. Sticks, flakes, pellets. Dissolution in water is highly exothermic. Strongly basic. Severe hazard to skin tissue White deliquescent solid. Sticks, flakes, pellets. Dissolution In water is highly exothermic. Strongly basic. Severe hazard to skin tissue White powder soluble in water yielding lime water. Alkaline Weakly alkaline. Emits ammonia gas. Severe eye irritant... 

Similarly, bases made from the metals of Group I on the periodic table, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH), are called monobasic because they release one hydroxide ion into solution. Bases made up of Group II metals, such as calcium hydroxide [Ca(OH)2] or magnesium hydroxide [Mg(OH)2], release two hydroxide ions and are therefore dibasic. Like acids, any base that is capable of releasing more than one hydroxide ion into solution is called polybasic. 

We can think of water entering the lake in terms of a titration. A solution of alkali enters a fixed volume of acid the alkaline solution is water entering from the lake s tributary rivers, and the acid is the lake, which contains the weak acid H2CO3 (carbonic acid) deriving from atmospheric carbon dioxide. The alkali in the tributary rivers is calcium hydroxide Ca(OH)2, which enters the... 

Titration of soil pH is an old method that is not widely used today. Basically, an acid soil suspension is prepared and titrated with a standardized base, often sodium hydroxide, although various basic calcium compounds such as calcium oxide (CaO) and calcium hydroxide [Ca(OH)2] can also be used. Because of the dark color of many soils, they are often titrated using a pH meter as the indicator of the end point. A setup for the titration of soil is shown in Figure 10.1. Titration is slow in that it takes some time after the addition of titrant for some semblance of equilibrium to be reached. Once this happens, a reading can be made or simply another addition of titrant made. 

Alkali metal (Group IA) hydroxides (LiOH, NaOH, KOH, RbOH, CsOH), Calcium hydroxide, Ca(OH)2, strontium hydroxide, Sr(OH)2, and barium hydroxide, Ba(OH)2... 

In Investigation 9-A, you will collect solubility data and use these data to determine a Ksp for calcium hydroxide, Ca(OH)2. When you calculate Ksp, you assume that the dissolved ionic compound exists as independent hydrated ions that do not affect one another. This assumption simplifies the investigation, but it is not entirely accurate. Ions do interfere with one another. As a result, the value of Ksp that you calculate will be just an approximation. iCp values that are calculated from data obtained from experiments such as Investgation 9-A are generally higher than the actual values. 

Calcium hydroxide [Ca (OH) ] is known as slaked or hydrated lime and is formed by exposing calcium oxide to water. Slaked lime is less caustic than quick lime. Therefore, it is used to line football fields. (Unslaked lime, CaO, is very caustic when wet, and if it is used on playing fields, players may receive caustic burns.) Calcium hydroxide has many uses, including as an ingredient for stonemasons mortar, cements, whitewash, and soil conditioner (high pH), as a food additive, and as a human depilatory. 

Concrete is made of cement aggregate and water mixed together to form a paste. The aggregate is usually a tiller material composed of inert ingredients such as sand and rocks. When water is added, the components of cement undergo a chemical reaction known as hydration. As hydration occurs, the silicates are transformed into silicate hydrates and calcium hydroxide (Ca OII 2), and the cement slowly forms a hardened paste. 

The most common chemical used in scruhhers today is limestone (calcium carbonate CaCOj) because it reacts with sulfur dioxide readily to form calcium sulfite (CaSOj), which can be collected and sold as gypsum. In recent years, a new scrubber design that uses lime (calcium hydroxide Ca(OH)2) rather than limestone has been introduced in many plants ... 

KOH), and calcium hydroxide, Ca(OH) j. Ammonia (NH 3) is a weak base, capable of reacting with H+ to form the ammonium ion,... 

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