Sodium hydroxide titration with nitric acid

Rivera-Utrilla and coworkers carried out adsorption studies of Co(ll) ions from aqueous solutions using activated carbons prepared from almond shell activated to different degrees by activation in CO2 at 1123 K, and after the formation of carbon-oxygen acidic surface groups on treatment with nitric acid, hydrogen peroxide, and in air, and carbon-nitrogen basic surface groups on treatment with ammonia. The surface acidity and the surface basicity of each carbon was determined by titration with sodium hydroxide and HCl solutions, respectively. The adsorption isotherms of Co(II) ions on three typical samples of carbons, namely commercial... 

Equations 9.41 and 9.42 represent the reactions that occur when solutions of nitric and sulfuric acid are titrated with sodium hydroxide ... 

Suggest suitable colour change indicators for the titration of (a) acetic acid (0.100 M) with sodium hydroxide (0.100 M) and (b) nitric acid (0.0100 M) with sodium hydroxide (0.0100 M). Give the reasons for your choice. 

Telluric acid can be titrated as a monobasic acid with standard sodium hydroxide using phenolphthalein as an indicator, if an equal volume of glycerol is added. If any nitric acid is present, it must be neutralized first with sodium hydroxide, using methyl orange as indicator. 

Discussion. When a solution of an orthophosphate is treated with a large excess of ammonium molybdate solution in the presence of nitric acid at a temperature of 20-45 °C, a precipitate is obtained, which after washing is converted into ammonium molybdophosphate with the composition (NH4)3[P04,12Mo03]. This may be titrated with standard sodium hydroxide solution using phenolph-thalein as indicator, but the end point is rather poor due to the liberation of ammonia. If, however, the ammonium molybdate is replaced by a reagent containing sodium molybdate and quinoline, then quinoline molybdophosphate is precipitated which can be isolated and titrated with standard sodium hydroxide ... 

Discussion. Arsenates in solution are precipitated as silver arsenate, Ag3 As04, by the addition of neutral silver nitrate solution the solution must be neutral, or if slightly acid, an excess of sodium acetate must be present to reduce the acidity if strongly acid, most of the acid should be neutralised by aqueous sodium hydroxide. The silver arsenate is dissolved in dilute nitric acid, and the silver titrated with standard thiocyanate solution. The silver arsenate has nearly six times the weight of the arsenic, hence quite small amounts of arsenic may be determined by this procedure. 

Procedure Weigh accurately about 0.2 g of chlorobutol in a flask and dissolve in 5 ml of alcohol. Add to it 5 ml of sodium hydroxide solution, and boil under a reflux condenser for 15 minutes. Cool, dilute with 20 ml of DW, add 5 ml of nitric acid, 1 ml of nitrobenzene and 50 ml of 0.1 N silver nitrate solution. Shake the contents vigorously for 1 minute, add 4 ml of ferric ammonium sulphate solution and titrate the excess of silver nitrate with 0.1 N ammonium thiocyanate solution. Each ml of 0.1N silver nitrate is equivalent to 0.005917 g of C4H7C130. 

Congo red is an indicator that changes colour in the pH range 3.0 to 5.0. Suppose that you are titrating an aqueous sodium hydroxide solution with nitric acid added from a burette. Is congo red a suitable indicator If so, explain why. If not, will the end-point occur before or after the equivalence point Explain your answer. 

Wang has determined citric acid and procaine in Xiaozhi injectable (an anti-hemorrhoid agent) by two-phase titration [81]. With constant shaking, a mixture of 1 1 1 2 Xiaozhi solution - water - chloroform -ethanol was titrated against 0.1 M sodium hydroxide to the phenolphthalein end point, thus obtaining the citric acid content. Dilute nitric acid was then added to the solution until the pink color disappeared, and the solution titrated against 0.1 M silver nitrate (with 5 drops of... 

For compounds containing chlorine or bromine, a weighed sample is dissolved in 10 ml. of methanol 10 ml. of 20% sodium hydroxide, 2 g. of zinc, and 0.5 g. of Raney nickel are added, and the mixture is heated with reflux for 1 hour over a water bath. It is then cooled and decanted. After acidification with nitric acid, 20 ml. of standard silver nitrate solution and 5 ml. of a ferric alum solution are added, and the solution is titrated with standard potassium thiocyanate. The procedure is modi-... 

The acid phase was divided into several portions that were used to make the following measurements. The total acidity (reported as percent sulfuric acid) was determined by titration with a standard sodium hydroxide solution using a methyl purple indicator. Total sulfuric acid was determined in a second sample in a similar manner after the nitric acid and lower oxides of nitrogen were expelled by evaporation on a steam bath. Lower oxides of nitrogen were determined by a redox method. Total nitric acid was determined by difference. 

Nitric acid in the aqueous phase was determined by the method used by Barduhn and Kobe(15), i.e. titration against st6uridard ferrous sulphate. Nitrous acid was ainalysed using formation of a diazonium salt between m-nitroaniline and nitrous acid. Standard m-nitroaniline solution was titrated against a known volume of the sample acidified with dilute hydrochloric acid until testing with starch iodide paper demonstrated the absence of free nitrous acid. The total acidity of the aqueous phase was obtained by titration against standard sodium hydroxide. 

Thus, the best condition of those tested for americium transfer Is O.IM nitric acid plus 6.9M sodium nitrate. Actual Rocky Flats waste streams may be brought to these conditions by titration with the appropriate amount of sodium hydroxide. A similar study of the transfer of plutonium (IV), using the same conditions shows a similar permeability, but the fraction transfered Is lower (70%). 

Dilute 10 ml to 100 ml with water in a graduated flask. To 10 ml add 40 ml of 0-05M EDTA, 90 ml of water and 015 ml of methyl red indicator. Neutralise with N sodium hydroxide, added dropwise, warm on a water-bath for thirty minutes and cool. Add 1 ml of dilute nitric acid (this is necessary, as otherwise there is insufficient acid to produce the required buffering action). Then add 5 g of hexamine and titrate with 0 05M lead nitrate using xylenol orange as indicator. 1 ml 0 05M - 0-001349 g Al. 

Weigh 0-3 g into a flask, add 120 ml of water and boil gently until dissolved. Cool, add 20 ml of O IN silver nitrate and 1-5 ml of phenol red indicator and titrate the liberated nitric acid with 0-lN sodium hydroxide to a deep red-violet colour. 1 ml 0-1N — 0-01802 g C7H8O2N4. 

Dissolve 0 5 g of theobromine and sodium salicylate in 100 ml of hot water, add 15 ml of 0-1N sulphuric acid and boil to remove carbon dioxide. C ool to 40, add 15 ml of phenol red solution and a measured quantity of O IN sodium hydroxide until the mixture is alkaline (2 to 3 ml required). Titrate with O IN sulphuric acid until the colour of the indicator changes to lemon yellow. The amount of 0 1 N sodium hydroxide deducted from the total 0-1N acid is a measure of the alkalinity. To this solution add 20 ml of O IN silver nitrate and titrate the liberated nitric acid with O IN sodium hydroxide to a deep red-violet colour. 1 ml O IN 001802 g theobromine. The approach of the endpoint is indicated by incipient precipitation of silver oxide. 

Boil about 10 g, accurately weighed, under reflux with 20 ml of 5 per cent ethanolic solution of sodium hydroxide for thirty minutes. Add 100 ml of water, acidify with dilute nitric acid and add 10 ml of O IN silver nitrate. Shake vigorously, filter, wash and titrate with 0-02N ammonium thiocyanate using iron alum as indicator. 1 ml 0 1 N AgN03 = 0 03545 g CijHyCl,. 

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