Sulphur chemistry on metals has been intensively studied as being particularly important in different technologies among which is metallurgy and metal corrosion. An example is the study by Hamilton and woods (Hamilton and Woods, 1981) who studied the products of sulphur oxidation of pyrite and pyrrhotite. In the floatation of sulphide minerals and base metal oxides, alkali sulphides have been widely used for a long time (Buswell and Nicol, 2002) which lead to extensive study of sulphur chemistry. In natural gas and crude oil industries, the effects of corrosion that sulphide ions have on iron based alloys has been well known. This goes to show the importance of sulphur chemistry to metallurgical engineers.
Pyrite oxidizes to both sulphur and
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The implication of this is that Sulphur is stable in the presence of water and in acidic conditions free from oxidizing agents. In alkaline conditions, it is unstable and tends to disproportionate to give HS–, S2– (and polysulfides), SO42−, and other oxidation products. In industrial applications, these reactions are slow and take place only in hot and very alkaline media. Sulphur is usually a major product of sulphur mineral oxidation at pH of 4.6. Increase in pH to 9 accompanied by an increase in potential results in the formation of sulphate ions (Hamilton and Woods, 1981).
From thermodynamic considerations, sulphur is expected to be easily oxidized to sulphate or bisulphate over a wide range of conditions. These can be seen from the small region of sulphur stability as depicted in Figure 3.1 and Figure 3.2 below. With increased temperature, the sulphur stability regions are reduced even further supporting the hypothesis of easy oxidation of sulphur over a wide range of conditions (Eh and pH). However, because of kinetic constraints, the sulphur stability range is considerably larger than that depicted by thermodynamics (Peters,
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Elemental sulphur has been noted as the end product of pyrite oxidation in acid media (low pH), but it is unstable in alkaline solutions. Thiosulphate was detected as an intermediate in anodic dissolution of pyrite (Mishra and Osseo-Asare, 1988). Studies conducted by Mycroft during electrochemical oxidation of pyrite (Mycroft et al., 1990) showed the formation of sulphur and polysulphide in near neutral aqueous solutions. However, in alkaline solutions, the formation of sulphur and polysulphide is only detected at higher potentials. On the contrary, Hamilton and Woods (Hamilton and Woods, 1981) operating at pH 9.2 suggested formation of monolayer sulphur during pyrite oxidation a potential of about 0.0
The chemical elements are divided into two broad groups, the metals and the non-metals. In this experiment, you will examine some members of the metal group and identify similarities and differences in their physical and chemical properties. Metals are the elements that are found in the left of the periodic table with high electrical and thermal conductivity. Metals lose electrons to create positive ion charges. Metals have a unique shine, are prone to forming, have a high tendency to form cations, and combine with oxygen to give mostly basic oxides.
Experiment VIII was performed to analyze SN2 and SN1 using tertiary and primary substrates and use gas chromatography (GC) to examine the SN1 reaction. The product of the SN2 reaction was classified as n-butyl iodide by using infrared spectroscopy and gas chromatography mass spectroscopy and the product of the SN1 reaction was identified as of t-butyl chloride by using infrared spectroscopy and gas chromatography. For the SN2 reaction, 7.62 grams of n-butyl bromide, 20.0 grams of sodium iodide, and 79.1 grams of acetone were used to produce 3.12 grams of n-butyl iodide. The limited reagent was identified as n-butyl bromide and the theoretical yield of n-butyl iodide was calculated as 10.3 grams. The percent yield of this reaction was calculated
The reaction between Hydrochloric Acid and Sodium Carbonate led to the formation of gaseous Carbon Dioxide, aqueous water, and aqueous solution of Sodium Chloride as a result of all compounds containing alkali metals solubility. Lastly, Copper Sulfate and Sodium Carbonate reaction produced an aqueous sodium sulfate solution and a solid precipitate of Copper (II) Sulfite because of all alkali metals and sulfates ability to be soluble and the rule that any compound containing CO₃ is insoluble. In the end, the hypothesis that if we react mystery chemicals with one another, we will be able to identify the reactants and products, create balanced equations, and observe properties because of our prior knowledge learned throughout the course of the unit and using the known chemical reaction was accepted by the data
The topic of this lab experiment is the relationship between percent yields and limiting reagents, and how it relates to copper (II) sulfate and aluminum foil. The objective was to determine the limiting reagent in a reaction and calculate the percent yield. To understand this, fundamental concepts of percent yields and limiting reagents are essential. A percent yield is defined as the ratio of the actual yield, to the theoretical yield in a reaction, expressed as a percent (Haberer, Salciccioli, & Sanader, 2011). This is useful as several impurities in this reaction possibly contributed to the percent yield.
Decomposition of copper sulfate pentahydrate (CuSO4●5H2O) Introduction: By now, you are aware that scientists apply heat to substances in order to decompose them. In this lab, you will apply heat to make copper sulfate pentahydrate (CuSO4●5H2O) undergo a decomposition reaction. You will make observations and will have to make an educated claim about the products of the decomposition reaction. Furthermore, you will have to use your observations as evidence and will have to discuss your reasoning about why your observations support your claim. 1.
Everyday Use and Sula are coming of age stories. They both illustrate times in people’s lives when they have to decide to how they are going to live with their past and themselves. The short story "Everyday Use", Alice Walker emphasizes the aspect of individuality. The story focuses on the lives of two sisters, Maggie and Dee.
Conclusions The experiment contained six ionic aqueous compounds that reacted and formed new products. The reactants were barium chloride, potassium nitrate, silver nitrate, sodium carbonate, calcium sulfate, and sodium phosphate. In Station 1, barium chloride and potassium nitrate did not react. Barium chloride and silver nitrate created aqueous barium nitrate and the precipitate silver chloride.
Purpose: The purpose of performing the 2 gram lab was to obtain 2.00 grams of our solid product, barium sulfate. In order for barium sulfate to be a product, we decided to perform a double replacement reaction. Background: In order for barium sulfate to be a product, we decided to perform a double replacement reaction.
Finding the empirical formula for hydrated copper sulfate using calculations to find the amount of each element present in the copper ion, sulfate ion, and water while also comparing the empirical formula to a literature value. Christian Cooper Alexis Powers CHM1210-18M/Gregory Bowers 11-5-15 Purpose: To begin, there are several different goals, techniques, and claims to note in the experiment involving hydrated copper sulfate. The overall goal of this experiment is to find the empirical formula and compare it with a literature value. Yet, in finding the empirical formula of hydrated copper sulfate, there are several process for it to get through, like finding the percentages of copper, water, and finally sulfate.
+ H2O (g) Reaction 4: when a sulphuric acid is added to the solution that contains copper (II) oxide, a double displacement reaction will occur. the copper (II) oxide will react with the sulphuric acid producing copper (II) sulfate and water. The copper and hydrogen gas replace each other. Balanced Chemical Equation: CuO (s) + H2SO4 (aq) —> CuSO4 (aq) + H2O (l) Reaction 5: when zinc is added to the copper (II) sulfate solution, a single displacement reaction will occur.
The results do not support the hypothesis that a higher surface area to volume ratio would result in sulphuric acid being diffused into the agar cubes in the shortest amount of time. This is evident in the results as the exact opposite to what was predicted occurred. Instead of the smallest cube with the largest surface area to volume ratio of 1cm3 having the quickest diffusion rate, it conversely took the longest at 0.092 cm3 per second, whilst the 2cm3 cube with 0.0384 cm3 per second took the least amount of time. This directly refutes the hypothesis. There was also no consistent trend evident in the results.
Further applications of reaction kinetics exploration could delve into the effects of environmental factors
Aim: To find out the relationship between the greater concentration of sodium thiosulfate when mixed with hydrochloric acid and the time it takes for the reaction (the time it takes for the solution to turn cloudy) to take place and to show the effect on the rate of reaction when the concentration of one of the reactants change. Introduction: The theory of this experiment is that sodium thiosulfate and hydrochloric acid reach together to produce sulfur as one of its products. Sulfur is a yellow precipitate so, the solution will turn to yellow color while the reaction is occurring and it will continue until it will slowly turn completely opaque. The reaction of the experiment happens with this formula: “Na2 S2 O3 + HCL =
Introduction The goal of the experiment is to examine how the rate of reaction between Hydrochloric acid and Sodium thiosulphate is affected by altering the concentrations. The concentration of Sodium thiosulfate will be altered by adding deionised water and decreasing the amount of Sodium thiosulphate. Once the Sodium thiosulphate has been tested several times. The effect of concentration on the rate of reaction can be examined in this experiment.
When surface water (H2O) reacts with sulphide minerals in coal heaps or exposed coal rocks it chemically reacts to produce acidic water such as sulphuric acid (H2SO4). STUDENT No. 48494070 STUDENT NAME: NOBLE KANYERA UNIQUE No. 603854 5 ASSIGNMENT 02