Carbon basicity determination

In this experiment students synthesize basic copper(ll) carbonate and determine the %w/w Gu by reducing the copper to Gu. A statistical analysis of the results shows that the synthesis does not produce GUGO3, the compound that many predict to be the product (although it does not exist). Results are shown to be consistent with a hemihydrate of malachite, Gu2(0H)2(G03) I/2H2O, or azurite, GU3(0H)2(G03)2. 

In general, the electrochemical performance of carbon materials is basically determined by the electronic properties, and given its interfacial character, by the surface structure and surface chemistry (i.e. surface terminal functional groups or adsorption processes) [1,2]. Such features will affect the electrode kinetics, potential limits, background currents and the interaction with molecules in solution [2]. From the point of view of electroanalysis, the remarkable benefits of CNT-modified electrodes have been widely praised, including low detection limits, increased sensitivity, decreased overpotentials and resistance to surface fouling [5, 9, 11, 17]. 

A wide variety of carbonaceous materials can intercalate or insert lithium reversibly and thus may be candidates for anodes for lithium ion batteries. In recent years, many types of carbons have been tested as alternative anodes for rechargeable lithium batteries, part of which have found use as anodes in practical, commercial lithium ion batteries. The most straightforward way of classifying these electrodes is according to the type of the carbon, which determines their capacity and basic electrochemical behavior. The major types of carbons tested in recent years as anode materials for Li ion batteries are listed below ... 

Thus, the ability of the model to predict the chemistry of heavy metals in brine in a sense was used to test the validity of the carbonate subroutine. The general procedure was to assume that the trace metal solubility in brine was controlled by either the carbonate, basic carbonate or hydrous oxide form of the metal. The heavy metal and carbonate ion activities were determined by the model. The resultant calculated solubility of the heavy metals in brine was then compared with experimentally determined values. 

Williams et al. also measured DOC (Dissolved Organic Carbon) at average values of 138 and 238 pM for the dry and wet seasons, respectively. The annual volume weighted mean of 159 pM implies an annual deposition of about 0.4 moles C m. The acidity was basically determined by the concentrations of organic acids. The concentration of acetate was 9 3 peq and formate was 2.9 peq hk The average conductivity was... 

Electrostatic interactions between the carbon surface and the active-phase precursors have also to be taken into account in the preparation of carbon-supported catalysts. The presence of oxygen functionalities on the carbon surface, which can be produced upon the activation process (for activated carbons) and/or by subsequent oxidation treatments, renders it amphoteric. This implies that it can be more or less charged, positively or negatively, depending on the pH of the surrounding solution. Preparation variables such as the polarity of the solvent, the pH of the solution, the anionic or cationic nature of the metal precursor, and the isoelectric point (lEP) of the carbon support determine the extent of precursor-support interaction and, in this way, the total uptake and dispersion of the active phase in the final catalyst [17,20,37]. Thus, for carbons containing acidic surface groups and, as a consequence, a low isoelectric point, best results in the preparation of supported catalysts are achieved when a cationic precursor is used in basic media. Under these conditions, the acidic complexes (-COOH, -OH) are deprotonated (-COO , -0 ) in such a way that... 

Nickel carbonate, basic Nickel sulfate Nickel sulfate hexahydrate nickel catalyst mfg., organic reactions Nickei formate nickei detection Dimethyi giyoxime nickei determination Dimethyi giyoxime 1,10-Phenanthroline monohydrate nickei eiectroforming Nickei suifamate nickei eiectropiating baths Boric acid nickei mfg. 

Loss on ignition measurements and levels of calcium hydroxide, calcium carbonate, basic carbonates, and organic material (e.g. from grinding aids) are determined by thermogravimetric analysis. This technique shows weight loss at characteristic temperatures that can be related to the amount of various phases present. Free (uncombined) lime (CaO) is determined by extraction with ethylene glycol and titration with O.lmoll hydrochloric 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... 

Some trends in the study of carbon monoxide and carbon dioxide hydrogenations over metal oxides and metal-metal oxide systems were examined in this chapter. These reactions usually take place over multicomponent and often multiphase catalyst systems with bifunctional sites, and produce HC and alcohols. The selectivity in these reactions is basically determined by the nature of the catalytic function, which determines largely the interaction of carbon oxides and hydrogen on the catalyst surface. CO binds to coordinatively unsaturated Zn + sites and acts as a... 

Introduction of disperse fillers (metals and their oxides) has an influence on anionic polymerization. The effect is connected with the presence of reactive surface centers such as OH-groups of various degree of acidity or basicity, metal cations, oxygen anions, admixtured atoms of metals, etc. Anionic polymerization at the surface of disperse carbons is determined by the possibihty of the formation of the clathrate compounds of alkaline metals and graphite. 

Source. Ref. 52. (The terms and definitions taken from ISO 10081-1 1991 Basic Refractory Products, Table 4.1 Types and Groups, are reproduced with the permission of the International Organization for Standardization, ISO. These standards can be obtained from any ISO member and from the web site of the ISO Central Secretariat at the following address www.iso.org. Copyright remains with ISO.) The analysis is carried out on the calcined products and the residual carbon is determined as in ISO 10060-1. 

A quantitative analysis for NH3 in several household cleaning products is carried out by titrating with a standard solution of HGl. The titration s progress is followed thermometrically by monitoring the temperature of the titration mixture as a function of the volume of added titrant. Household cleaning products may contain other basic components, such as sodium citrate or sodium carbonate, that will also be titrated by HGl. By comparing titration curves for prepared samples of NH3 to titration curves for the samples, it is possible to determine that portion of the thermometric titration curve due to the neutralization of NH3. 

Acid-Base Behavior. The relative acidity-basicity of the filler, generally determined by measuring the pH value of a slurry of a specific mass of filler in 100 mL of deionized water, can influence the behavior of a filler in some systems. For example, the curing behavior of some elastomers is sensitive to the pH value of carbon black. 

Quantitative Analysis of All llithium Initiator Solutions. Solutions of alkyUithium compounds frequentiy show turbidity associated with the formation of lithium alkoxides by oxidation reactions or lithium hydroxide by reaction with moisture. Although these species contribute to the total basicity of the solution as determined by simple acid titration, they do not react with allyhc and henzylic chlorides or ethylene dibromide rapidly in ether solvents. This difference is the basis for the double titration method of determining the amount of active carbon-bound lithium reagent in a given sample (55,56). Thus the amount of carbon-bound lithium is calculated from the difference between the total amount of base determined by acid titration and the amount of base remaining after the solution reacts with either benzyl chloride, allyl chloride, or ethylene dibromide. 

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