Direct titration methods

In usual practice, the volumetric titrations may be accomplished either by direct titration method e.g., assay of HC1 employing NaOH as the titrant, or by residual titration method e.g., assay of ZnO in which case a known-excess-measured volume of standardised solution of H2S04, more than the actual amount chemically equivalent to ZnO, is added to the sample thereupon, the H2S04 which remain unreacted with ZnO is subsequently titrated (sometimes referred to as back titration or residual titration in the text) employing standardized NaOH solution. 

The two methods, namely direct titration method and residual titration method are briefly discussed as under ... 

A few typical examples of acidimetric titrations, employing direct titration method (DTM) and residual titration method (RTM) from the Pharmacopoeia of India are described here ... 

What do you understand by direct titration method in the context of Aqueous Titrations Discuss in details the procedure involved in the assay of ... 

Hydrogen peroxide solution and potassium bromide are two pharmaceutical substances that may be estimated by employing 0.1 N potassium permanganate solution and adopting the direct titration method. 

J) Direct titration method, (ii) Indirect titration method, and... 

Discuss direct titration method using dichromate method in the assay of Iron Ore with reference to the following aspects ... 

Give a comprehensive account of the direct titration method with silver nitrate with reference to the following ... 

A number of pharmaceutical inorganic substances may be assayed by the direct titration method using disodium ethylenediaminetetracetate. A few typical examples are cited in the following Table 9.2. 

Direct titration method offers a serious limitation for the assay of aluminium and bismuth containing pharmaceutical inorganic substances because of the precipitation of the metal as their corresponding hydroxides in alkaline media thereby introducing undesirable errors. 

How would your carry out complexometric btrations by the direct titration method Discuss the assay of the following pharmaceutical drugs explicitely ... 

C)LA Content. Several methods are known of which the following direct titration method described by J.D. Hopper O.E. Burton in PATR 255 (1932) seems to be the simplest, although it is not as accurate as the gas-ometric method used by the US Ordnance Corps... 

Due to the fact that doubts have been expressed concerning the validity of the values obtained from the assay of the gasometric method of analysis,Croom Pristera of Pic Arsn (Ref 15) investigated this method. They also studied the US Navy distillation-titration method and the British direct titration method not only from the point of view of their precision but also of their applicability to LA s contg additives, inorganic (Pb carbonate in Brit "Service LA) or organic (dextrin, PVA, etc)... 

Although less commonly employed than indirect titration methods, soil scientists also used direct titrations methods to study the acid-base chemistry and metal interactions of soil organic matter (PommerandBreger, 1960 Posner, 1966 Gamble, 1970, 1972 van Dijk, 1971 Khalaf et al, 1975 ... 

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