Hydrochloric acid equivalent mass

The standard redox potential is 1.14 volts the formal potential is 1.06 volts in 1M hydrochloric acid solution. The colour change, however, occurs at about 1.12 volts, because the colour of the reduced form (deep red) is so much more intense than that of the oxidised form (pale blue). The indicator is of great value in the titration of iron(II) salts and other substances with cerium(IV) sulphate solutions. It is prepared by dissolving 1,10-phenanthroline hydrate (relative molecular mass= 198.1) in the calculated quantity of 0.02M acid-free iron(II) sulphate, and is therefore l,10-phenanthroline-iron(II) complex sulphate (known as ferroin). One drop is usually sufficient in a titration this is equivalent to less than 0.01 mL of 0.05 M oxidising agent, and hence the indicator blank is negligible at this or higher concentrations. 

Erk presented a ratio spectra derivative spectrophotometric method and a Vierordt s method for the simultaneous determination of hydrochlorothiazide in binary mixtures with benazepril hydrochloride, triametrene, and cilazapril [19]. A mass of powder equivalent to one tablet was dissolved in 1 1 methanol/0.1 M Hydrochloric acid (solvent A), shaken for 30 min, filtered and the residue was washed with 3x10 mL of solvent A. Combined solutions were diluted to 100 mL with solvent A, and then diluted with methanol for analysis by (i) Vierordt s method, and (ii) ratio spectra derivative spectrophotometry. For method (i), the absorbance of the solution was measured at 271.7, 238.1, 234.1, and 210.7 nm for hydrochlorothiazide, benazepril, triametrine, and cilazapril, respectively, and the corresponding concentrations were calculated using simultaneous equations. For method (ii), the absorption spectra of solutions containing different amounts of hydrochlorothiazide in a... 

Let us derive the formulas for calculating the quantities of sulfuric acid, hydrochloric acid, and nitric acid and the formulas for calculating the quantities of caustic soda and soda ash that may be needed to lower and to raise the pH, respectively. To find the equivalent masses of the acids, they must be reacted with the hydroxyl ion. Reaction with this ion is necessary, since total alkalinity may be represented by the hydroxyl ion. Remember that the acids must first consume all the existing alkalinity represented in the overall by the OH before they can lower the pH. Thus, proceed as follows ... 

From these equations, the equivalent masses are sulfuric acid = H2SO4/2 = 49.05, hydrochloric acid = HCFl = 36.5, and nitric acid = HNO3/I = 63.01. 

Let Me so pH. ecipe. and MhnOjph be the kilograms of sulfuric acid, hydrochloric acid, or nitric acid used to lower the pH from the current pH to pH, . Gleaning from Equation (13.54) and the respective equivalent masses of H2SO4, HCl, and HNO3 and the cubic meters, V, of water treated. 

As shown in Equation (17.9), a mole of hydrochloric acid is produced per mole of chlorine gas that reacts. Chlorination uses up the disinfectant, so this reaction would be driven to the right and any mole of chlorine gas added will be consumed. Thus, if a mmol/L of the gas is dosed, this will produce a mmol/L of HCl. This is equivalent to one mgeq of the acid, which must also be equivalent to a mgeq of alkalinity. The analytical equivalent mass of alkalinity in terms of CaCOj is 50 mg CaCOs per mgeq. Thus, the mmol/L of hydrochloric acid produced will need 50 mg/L of alkalinity expressed as CaCOs for its neutralization. Or, simply, one mmol of hydrochloric acid requires 50 mg of alkalinity expressed as CaCOs for its neutralization. 

On a commercial scale uranous oxide is prepared by fusing at red heat a mixture of 35 parts of common salt and 20 parts of sodium uranate with 1 part of powdered charcoal, the heating being continued until the escape of gas ceases. After cooling, the mass is lixiviated with water, and the residue of uranous oxide is washed by decantation. By washing with 5 per cent, hydrochloric acid, any iron, aluminium, or vanadium compounds may be removed, and a commercial product of purity equivalent to 97 per cent. U3O3 is obtained. If the uranous oxide is required for the production of ferro-uranium, the complete removal of iron is not necessary. 

Three molar equivalents of bromine is added with cooling to a mixture of 1 molar equivalent of quinoline and 3 gram-atom equivalents of sulfur, and the resulting mixture is heated to 180-200" in an oil bath for 2 hours. The cooled reaction mass is extracted several times with hot concentrated hydrochloric acid, and the combined extracts are made alkaline with sodium hydroxide. Ether extraction of the alkaline mixture followed by distillation of the ethereal solution gives a 50% yield of 3-bromoquinoline boiling at 158—162°/24 mm. 

To standardize a hydrochloric acid solution, it was used as titrant with a solid sample of sodium hydrogen carbonate, NaHCOs. The sample had a mass of 0.3967 g, and 41.77 mL of acid was required to reach the equivalence point. Calculate the concentration of the standard solution. 

Five grams of tellurium dioxide is dissolved in 15 ml. of concentrated hydrochloric acid, and the solution is evaporated to 7.5 ml. A saturated solution of two molal equivalents of ammonium chloride (3.5 g. in about 12 ml. of water) is added and the evaporation continued on a steam bath tmtil a mass of glistening yellow crystals is formed. The crystals are carefully drained on a filter and then dried in a vacuum desiccator over soda lime. Yield 8.2 to 9.6 g. (70 to 82 per cent). The product hydrolyzes in moist air to give tellurium dioxide. 

A 4.36-g sample of an unknown alkali metal hydroxide is dissolved in 100.0 mL of water. An acid-base indicator is added and the resulting solution is titrated with 2.50 M HCl(oq) solution. The indicator changes color signaling that the equivalence point has been reached after 17.0 mL of the hydrochloric acid solution has been added, (a) What is the molar mass of... 

What mass of magnesium hydroxide would be required for the magnesium hydroxide to react to the equivalence point with 558 mL of 3.18 M hydrochloric acid ... 

In the case of an acid-base reaction,/eq is chosen in such a way that only one proton exchange is considered during the titration reaction. For example, hydrochloric acid can liberate only one proton per mole. Hence, its equivalent is equal to its molar mass, and its equivalent factor is equal to 1 ... 

Neutralisation reactions. The equivalent of an acid is that mass of it which contains 1.008 (more accurately 1.0078) g of replaceable hydrogen. The equivalent of a monoprotic acid, such as hydrochloric, hydrobromic, hydriodic, nitric, perchloric, or acetic acid, is identical with the mole. A normal solution of a monoprotic acid will therefore contain 1 mole per L of solution. The equivalent of a diprotic acid (e.g. sulphuric or oxalic acid), or of a triprotic acid (e.g. phosphoric( V) acid) is likewise one-half or one-third respectively, of the mole. 

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