Calcium carbide hydroxide

Calcium carbide Moisture, selenium, silver nitrate, sodium peroxide, tin(II) chloride, potassium hydroxide plus chlorine, HCl gas, magnesium... 

Calcium carbide, CaC2, reacts with water to form calcium hydroxide and the flammable gas ethyne (acetylene). This reaction was once used for lamps on bicycles, because the reactants are easily transported, (a) Which is the limiting reactant when 1.00 X 102 g of water reacts with 1.00 X 102 g of calcium carbide (b) What mass of ethyne can he produced (c) What mass of excess reactant remains after reaction is complete Assume that the calcium carbide is pure and that all the ethyne produced is collected. The chemical equation is... 

This reaction shows that the methide ion is a very strong Bmnsted base. The species C22 is the acetylide ion, and the carbides that contain it are called acetylides. The acetylide ion is also a strong Bronsted base, and acctylides react with water to produce ethyne (acetylene) and the corresponding hydroxide. Calcium carbide, CaC2, is the most common saline carbide. 

Dimethylethynyl carbinol has usually been prepared by the addition of acetylene to the sodium derivative of acetone,3 4 5 6 7>8 but potassium metal9 and sodium ethoxide10 have also been used. The above method is based upon that described by Sung Wou-seng.3 A more recent method uses potassium hydroxide, calcium carbide, and acetone.11... 

One of the most important discoveries in the history of the chemical industry in Ontario was accidental. Thomas Carbide Willson (1860-1915) was trying to make the element calcium from lime, CaO, by beating tbe lime with coal tar. Instead, he made the compound calcium carbide, CaC2. This compound reacts with water to form a precipitate of calcium hydroxide and gaseous ethyne (acetylene). Willson s discovery led to the large-scale use of ethyne in numerous applications. 

Calcium carbide (CaC ) has a garlic-like odor and reacts with water to form acetylene gas plus calcium hydroxide and heat. In the past, it was used in miners lamps to continuously produce a small acetylene flame to provide some illumination in coal mines. 

Thermal reduction processes are not being practiced anywhere in the world at present for large-scale production of sodium. Such methods, however, can he conveniently adapted for laboratory preparation of metalhc sodium. Sodium can be prepared by thermal reduction of its hydroxide, carbonate, or chloride at elevated temperatures. These salts are heated with carbon, calcium carbide, iron carbide, ferrosilicon, or other reducing agents at temperatures above 800°C under vacuum ... 

In a 2-1. three-necked flask (Note 1), fitted with a dropping funnel, condenser (equipped with a Drierite tube), and efficient stirrer driven by a powerful motor, is placed a mixture of 600 ml. of benzene, 48 g. (0.85 mole) of potassium hydroxide (Note 2), and 76.4 g. of powdered calcium carbide (Note 3). While this mixture is being stirred vigorously, 85 g. (0.87 mole) of cyclohexanone is added over a period of 0.5-1 hour. The mixture is dark gray and will become warm, but no external cooling is necessary. Stirring is continued, and within 24 hours the contents congeal (Note 4). This semisolid is allowed to stand for an additional 4 days (Note 5). 

Calcium Arsenate Calcium Phosphate Calcium Carbide Calcium Chlorate Calcium Chloride Calcium Chloride Calcium Chloride Calcium Chromate Calcium Chromate Calcium Chromate Calcium Cyanide Calcium Peroxide Calcium Fluoride Calcium Hydroxide Calcium Hypochlorite Calcium Phosphate Calcium, Metallic Calcium Nitrate Calcium Nitrate Calcium Oxide Calcium Peroxide Calcium Phosphate Calcium Phosphate Calcium Phosphide Calcium Resinate Calcium Resinate Calcium Resinate Calcium Phosphate Mercuric Chloride Mercurous Chloride... 

Assemble an apparatus for preparing acetylene (see Fig. 54). Put about 5 g of calcium carbide into 25-ml round-bottomed flask 1. Fill dropping funnel 2 and cylinder 3 with a 25% sodium chloride solution. Pour a little of a 1-2% sodium hydroxide solution into wash bottle 4, and a 2% potassium dichromate solution acidified with a dilute sulphuric acid solution into test tube 5. By adding the sodium chloride solution in small portions to the calcium carbide, achieve a uniform stream of gas. When the apparatus is filled with pure acetylene, test the gas for the absence of air in it. How can this be done ... 

Other foundries have investigated the recharging of the entire mass to the remelting furnace (Stephens 1988). Inside the furnace, calcium hydroxide forms in the slag as the recycled calcium carbide either removes additional sulfur or is directly oxidized. While this method has been successful, much work still remains to be done. For example, it is not known if the calcium sulfide stays with the slag or if the sulfur is emitted in the flue gas. Initial tests indicate that the sulfur does not concentrate in the metal so that product quality is not affected. 

Foundries that generate furnace dusts that are EP-Toxic due to lead and cadmium have found that by carefully mixing the dusts with water treated calcium carbide desulfurization slag (which contains calcium hydroxide), they may be rendered non-EP-Toxic. Great care must be taken with this method since at high pH levels the lead may leach out. In addition to this problem, the effect of other hazardous materials in the dust and in the slag may still render this waste as hazardous (Stephens 1988). 

One common practice is to treat the desulfurization slag with water (Stolzenburg, ec al., 1985). This is done to generate and release acetylene gas from the unreacted calcium carbide. The other major reaction product is solid calcium hydroxide or lime. 

When this is done, the calcium hydroxide is included in the melting furnace slag, and the unspent calcium carbide is either used or oxidized in the melting furnace. Little testing has been done to determine the actual fate of the sulfur. Most of it may be included in the slag, but it may also be emitted to the air as sulfur dioxide, or, for foundries with wet emission control systems, it may be dissolved in the water. 

Calcium Carbide. CAS 75-20-71. CaC . grayish-black solid, reacts with water yielding acetylene gas and calcium hydroxide, formed at electric furnace temperature from calcium oxide and carbon. 

Calcium carbide, CaC2, reacts with water to form calcium hydroxide and the flammable gas ethyne (acetylene). This reaction was once used for lamps on bicycles, because the reactants were easily transported. For this calcula-... 

Write a balanced equation for the reaction in which calcium carbide, CaC2, reacts with water to form ethyne and calcium hydroxide. 

Miners and spelunkers use a lamp fueled by water combined with calcium carbide (CaC2) to produce the flammable acetylene (C2H2) and the waste product calcium hydroxide (Ca(OH)2) ... 

A primary method for the manufacture of acetylene is to react calcium carbide, the principal raw material, with water to produce acetylene with calcium hydroxide as a byproduct ... 

Electrolytic processes are gradually displacing the older ehemical methods of isolating sodium dependent on the reduction of the carbonate or hydroxide with charcoal or iron.5 On a small scale, magnesium can be employed as reducer. A laboratory method is the reduction of the peroxide with wood-charcoal, coke, graphite, or calcium carbide 7... 

All technical processes for the synthesis of hydrazine yield either hydrazine in aqueous solution or hydrazine hydrate. Most applications can use hydrazine hydrate, but for some applications, for example, rocket propulsion, anhydrous hydrazine is necessary. The water can be removed by a chemical reaction followed by distillation or by azeotropic distillation with an auxiliary fluid. As water binding chemicals, calcium carbide, sodium hydroxide, calcium oxide, calcium hydride, barium oxide, barium hydroxide, and barium pemitride Ba3N4 have been used. The use of sodium or calcium metal and sodium amide is best avoided because of the formation of explosive hydrazides. Starting from hydrazine hydrate (64% hydrazine), sodium hydroxide is generally used... 

A by-product from the reaction of acetone and sodium acetylide is the acetylenic diol, (CHj)2C(OH)C= C(OH)(CH,)j, formed by condensation of two molecules of acetone with one molecule of sodium acetylide. A general method for the preparation of acetylenic diols of this type is from calcium carbide, potassium hydroxide, and ketones. Ciethynyl glycols in which the triple bonds are separated by two or four carbon atoms are made from sodium acetylide and a- or /S-diketones. ... 

Consider the reaction between solid calcium carbide and liquid water to form solid calcium hydroxide and gaseous acetylene ... 

Equations 9.1-1 and 9.1-2 together signify that if 1 mol of solid calcium carbide reacts completely with 2 mol of liquid water to form 1 mol of solid calcium hydroxide and 1 mol of gaseous acetylene, and the initial and final temperatures are both 25°C and the initial and final pressures are both 1 atm. then Hproducts ffreaciams = -125.4 kj. If the reaction is run under conditions such that the energy balance reduces to 2 = 125.4 kJ of heat must be transferred... 

A 200-ml, Soxhlet extractor is mounted between a one-neck flask and a reflux condenser, the condenser carrying a calcium chloride drying tube at the top. Calcium carbide is placed in the extractor thimble, and a mixture of 175 g. (1.29 moles) of o-toluic acid [Org. Syntheses Coll. Vol. 2, 588 (1943)], 1.2 1. of absolute ethanol, and 4 ml. of concentrated sulfuric acid is placed in the flask. The mixture is heated to reflux for 24 hours, after which the excess ethanol is recovered by distillation. The residual material is washed with 10% aqueous sodium hydroxide, and the mixture is extracted with benzene if necessary to obtain clean separation of the layers. The organic layer is distilled to give 155 g. (76%) of ester, b.p. 88-92 /5 mm. 

Desulfurization of hot iron by addition of calcium carbide leads to formation of a slag containing calcium sulfide and hydroxide as well as substantial amount of iron oxides. This slag is completely different than other metalurgical slags and may be effectively used for treatment of various acidic dr neutral wastewater containing heavy metal cations by hydroxide/sulfide precipitation, and, by removal of several components from wastewater by sorption and other interactions with iron oxides. 

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