Saturday, February 29, 2020

Calcium carbonate

Calcium carbonate Essay Outline1 4.1INTRODUCTION2 4.2AIMS AND OBJECTIVES3 Chapter 24 5.THEORY A ; METHOLOGY5 5.1PRINCIPLE OF THE EXPERIMENT6 5.2APPARATUS AND EQUIPMENTS7 Mortar and pestle Conical flasksWhite tile8 Filter funnelFiltter paper25.00 cm3 pipette9 5.3CHEMICAL USED10 2 M HCl Phenolphthalein11 2 M NaOH12 5.4PROCEDURE13 Chapter 314 6.EXPERIMENTAL Consequence15 6.1THE COLOR CHANGE OF THE SOLUTION16 6.2THE TITRATION RESULT OF BROWN EGG17 6.3THE TITRATION RESULT OF WHITE EGG18 119 220 321 Volume of eggshells solution/cm322 25.0023 25.0024 25.0025 Volume of NaOH used/cm326 20.4027 20.3528 20.0029 Chapter 430 7.CLCULATIONS31 7.1CALCULATIONS32 7.1.1 FOR BROWN EGG33 7.1.2 FOR WHITE EGG34 Chapter 535 8.DISCUSSION AND CONCLUTION36 8.1CONCLUSION37 8.2DISCUSSION38 Beginning of mistakes39 9. Reference 4.1INTRODUCTION Calcium carbonate, CaCO3, is found in nature giving hardness and strength to things such as seashells, stones, and eggshells. Equally difficult as this substance is, it will respond readily with hydrochloric acid to give C dioxide gas ( and two other merchandises ) . In this experiment pupils will plan an experiment by responding eggshells with 2 M HCl to compare the Ca carbonate composing of white ( poulet ) eggshells to brown eggshells. A good quality eggshell will incorporate, on norm, 2.2 gms of Ca in the signifier of Ca carbonate. Approximately 94 % of a dry eggshell is calcium carbonate and has a typical mass of 5.5 grams,1 although these values can differ depending on beginnings. Sums every bit low as 78 % have been published. The staying mass is composed mostly of P and Mg, and hint sums of Na, K, Zn, manganese, Fe, and Cu. In the instance of brown versus white eggs, a unequivocal difference in Ca carbonate sums may be difficult to bring out. However, see this. The colour of the eggs is nil more than a consequence of a different strain. The quality, nutritionary value, and gustatory sensation are indistinguishable between white and brown eggs, though two noteworthy differences are size and monetary value. Brown eggs are normally larger and somewhat more expensive. The ground for the monetary value addition is because brown eggs come from larger biddies, which need to be fed more nutrient daily. With a larger c onsumption of Ca each twenty-four hours, one might anticipate the produced egg to hold a higher Ca carbonate content. However, since the eggs are larger, it must be kept in head that the Ca is spread over a larger surface country during egg formation. A brown eggshell s increased inclination to interrupt, when compared to white, is frequently attributed to this â€Å"thinning out† of Ca during deposition. To avoid the breakage of eggs before making market, the eggshells needs to be every bit strong as possible. The strength of eggshells is chiefly determined by the per centum of Ca carbonate in it. In order to supervise the quality of eggshells, the undermentioned experiment has to be done to find the per centum of Ca carbonate in eggshells.In this experiment, back titration is used. First, extra acid is reacted with the Ca carbonate in eggshells. 2HCl ( aq ) +CaCO3 ( s ) >CaCl2 ( aq ) +H2O ( cubic decimeter ) +CO2 ( g ) Subsequently, if we can happen out the figure of mole of unreacted acid, figure of mole of Ca carbonate can so be found out. The figure of mole of unreacted acid can be found by titration with the undermentioned reaction. HCl ( aq ) +NaOH ( aq ) >H2O ( cubic decimeter ) +NaCl ( aq ) Percentage by mass of Ca carbonate in eggshell can so be calculated by the undermentioned expression: 4.2AIMS AND OBJECTIVES The intent of this experiment is to find the per centum by mass of Ca carbonate in eggshells. READ: I would remind you that extremism in the defense o Essaydesign an experiment that quantifies the sum of Ca carbonate nowadays in a natural substance. associate the sum of a reactant or merchandise of a chemical reaction to another reactant or merchandise. work collaboratively with their equals to work out a given job in the research lab in a manner that theoretical accounts the scientific method. use a common acid reaction between hydrochloric acid and the carbonate ion. Chapter 2 5.THEORY A ; METHOLOGY 5.1PRINCIPLE OF THE EXPERIMENT During this experiment, the per centum of CaCO3 in an eggshell is determined by responding the eggshell with hydrochloric acid. The equation for this reaction is: 2HCl ( aq ) + CaCO3 ( s ) >Ca2+ ( aq ) + CO2 ( g ) + H2O ( cubic decimeter ) + 2Cl- ( aq ) This reaction can non be used straight titrate with the CaCO3. Alternatively, an surplus of hydrochloric acid is added to fade out the eggshell, and the staying acid is titrated with NaOH solution to find the sum of acid that did non respond with the eggshell. The equation used to find the sum of remnant acid is: HCl ( aq ) + NaOH ( aq ) > H2O ( cubic decimeter ) + Na+ ( aq ) + Cl- ( aq ) 5.2APPARATUS AND EQUIPMENTS eaker Pipette FillerElectronicbalance Volumetric flaskBuretteWash bottle Mortar and pestle Conical flasksWhite tile Filter funnelFiltter paper25.00 cm3 pipette 5.3CHEMICAL USED 2 M HCl Phenolphthalein 2 M NaOH 5.4PROCEDURE White and Red coloring material eggshells have taken and the protein membrane was removed on the interior of the eggshells. The eggshell was washed with distilled H2O Dried in an oven for few proceedingss. The eggshell was so grounded into all right pulverization by howitzer and stamp. 2g of eggshell pulverization is weighted accurately by utilizing an electronic balance and it was transferred to a conelike flask. 25.00 cm3 of HCl was pipetted to fade out the eggshell pulverization. Distilled H2O was added to the flask until it reached about 100cm3. The flask was swirled gently. Put the solution into cubed for two yearss. Faltered the solution utilizing filter documents. Pippet out 25.00 cm3 from each solutions to titration flasks. The solution was so titrated with standardised NaOH. Repeat another two samples from each solution. Roll up the right burette readings at the terminal point. Chapter 3 6.EXPERIMENTAL Consequence 6.1THE COLOR CHANGE OF THE SOLUTION White egg Brown egg Colourless pink Colourless pink 6.2THE TITRATION RESULT OF BROWN EGG 1 2 3 Volume of eggshells solution/cm3 25.00 25.00 25.00 Volume of NaOH used/cm3 20.10 19.90 20.10 Average volume of NaOH used: ( 20.10+19.90+20.10 ) = 20.03cm33 6.3THE TITRATION RESULT OF WHITE EGG 1 2 3 Volume of eggshells solution/cm3 25.00 25.00 25.00 Volume of NaOH used/cm3 20.40 20.35 20.00 *Average volume of NaOH used: ( 20.40+20.35+20.00 ) =20.25cm33 Chapter 4 7.CLCULATIONS 7.1CALCULATIONS 2HCl ( aq ) + CaCO3 ( s ) >Ca2+ ( aq ) + CO2 ( g ) + H2O ( cubic decimeter ) + 2Cl- ( aq ) HCl ( aq ) + NaOH ( aq ) > H2O ( cubic decimeter ) + Na+ ( aq ) + Cl- ( aq ) 7.1.1 FOR BROWN EGG Number of moles of NaOH used to respond with HCl =20.03cm3 /1000 ) X2M = 40.06X 10-3 mol Since figure of moles of NaOH = figure of moles of HCl in 25cm3 =40.06 X 10-3 mol HCl mols in 100cm3 = 40.06 Ten 10-3 Ten 4 mol The initial no of moles of HCl: volume X molar concentration = 100/1000 X2M = 200X10-3 mol Number of moles of HCl used to respond with CaCO3 = ( 200X10-3 160.24X 10-3 ) mol = 39.76X10-3 mol Harmonizing to the equation, one mole of HCI required to respond with 2 moles of CaCO3, Number of moles of CaCO3 reacted =39.76X10- 3 /2 = 19.88X10-3 mol The weight of CaCO3 = 19.88X10-3g X100g The % of CaCO3 in eggshell ( brown ) = ( 1.988/2 ) X100 % =99.4 % 7.1.2 FOR WHITE EGG Number of moles of NaOH used to respond with HCl: ( 20.25cm3/1000 ) X2 = 40.50X10-3mol Since figure of moles of NaOH=number of moles of HCl in 25cm3 = 4.50X10-3mol HCl Volume in 100cm3 = 40.50 X10-3 X4 mol The initial moles of HCl: volume X molar concentration = 100/1000 X2M = 200X10-3 mol Number of moles of HCl used to respond with CaCO3: ( 200X10-3 162X10-3 ) mol = 38X10-3 mol Number of moles of CaCO3 reacted =38X10-3/2 = 19X10-3 mol The weight of CaCO3 = 19X10-3g X100 The % of CaCO3 in eggshell ( white ) = ( 1.9/2 ) X100 % =95.0 % Chapter 5 8.DISCUSSION AND CONCLUTION 8.1CONCLUSION Percentage of CaCO3 in ruddy eggshells= 99.4 % Percentage of CaCO3 in white eggshells= 95.0 % Therefore ruddy eggshells has the higher per centum of CaCO3. 8.2DISCUSSION Beginning of mistakes The eggshell pulverization did non fade out wholly Variation in ocular judgement at the terminal point Instrumental mistakes of the electronic balance The eggshell was non to the full dried Some droplets of solution may still adhere on the beaker and the glass rod which lead to the decrease in figure of moles of extra HCl In this Experiment we can besides make the EDTA titration. 9. Reference hypertext transfer protocol: //www.google.lk/search? hl=en A ; source=hp A ; q=caco3+percentage+in+eggshell A ; btnG=Google+Search A ; meta= A ; aq=f A ; oq= hypertext transfer protocol: //wwwchem.csustan.edu/chem1102/Egg.htm hypertext transfer protocol: //www.oppapers.com/essays/Determine-Percentage-Mass-Calcium-Carbonate-Eggshells/165593 hypertext transfer protocol: //ag.ansc.purdue.edu/poultry/multistate/koelkebeck1.htm

Thursday, February 13, 2020

Parpgraising paragragh about phosphene and alkynyl legand Essay

Parpgraising paragragh about phosphene and alkynyl legand - Essay Example Large variety of phosphines are thus possible, while different widely available verities include 1,1’ (BINAP) and 2,2’-bis (diphenylphosphino). In such chiral systems, steric constraints come up, that can be resolved into diastereomers. While discussing reactivity of complexes belonging to phosphine ligands, two properties of these ligands are considered important. These properties relate to their steric bulk and their accepting ability, also called electron donating ability. (d-Metal OGANOMETALLIC CHEMISTRY) Like alkyl groups, alkynyl, alkenyl and aryl groups can bond to a metal form through a single carbon atom. For this property, these groups are described as â€Å"monohapto’. However, there is a possibility of each of these three groups accepting â€Å"pai† electron density into anti-bonding orbitals, although the same has not been observed, largely, so far. This can be ratified by an example, which shows little change in the stretching frequency of the triple bond in alkynyl complexes, as they attach to a metal; although â€Å"n-1 –alkynyl group† might be considered analogous to a CO group. As per d-metal organometallic chemistry noting, the displacement of halide with a lithium reagent at a metal center can make way for introduction of alkynyl groups into organometallic complexes. While looking at the donor-pair scheme of electron counting, alkynyl ligands are considered to be two-electron donors with a single negative charge. (alkenyl, alkynyl and aryl

Saturday, February 1, 2020

Case Study - Writing a Management Consulting Letter to client Amanda

- Writing a Management Consulting Letter to client Amanda - Case Study Example Expansion should thus depend on social and economic factors such as consumer tastes and preferences. Through planning, Amanda and his workers can describe what they want to achieve and how they want to achieve it by providing a detailed description of how the objectives will be realized. Organizing human, physical and financial resources Amanda should develop and evaluate procedures that support the mission of the business and address specific needs. Failing to determine the best way to organize resources including personnel and resources may be a recipe for organizational failure. She should apply accepted management principles and practices that relate to personnel, financial and operational issues that directly affect the business. Having a well-written policy helps the business to address the procedures that support the needs of the business and its programs (Siobham, Morley & Forley, 2013). Human, physical, and financial resources are needed by this young firm in order to achiev e its vision and they should be strategically aligned in such a manner as to meet the organization's goals. She should realize that human, capital, and financial resources are transformational tools to an institution and enable it to achieve its functions. People who manage the business are an important component of its success and they should distinguish themselves with diligence, innovation, and dedication to the mission of the business (Robbins & DeCenzo, 2010; Shuck & Wollard, 2009). Each person should have his duty clearly defined and targets set within required timeframes to avoid laxity within the business. He should also share and develop the mission statement each time they are in a managerial meeting (Taylor, 2010). Perhaps the most difficult aspect of the organization is to handle the financial resources since there are several key components that need to be considered (Raja & Palanchamy, 2011). Leadership skills Leadership and management must go hand in hand since they a re linked together in business even though they are not the same (Perkins, 2008). Any effort by a business whether big or small to separate the two functions of a business is a recipe for failure and more problems for the business. As a manager, Amanda should plan, organize, and coordinate all the activities of the business and the same time acts as a leader by inspiring and motivating the employees of his small firm. Employees of today look at their manager as a leader and he should not assign trust but define for them a purpose in their jobs (Jackson, Meyer & Wang, 2012). She should organize workers to maximize efficiency and to nurture, develop talent and inspire results and this will ensure that the company remains effective and profitable with time (Wollard & Shuck, 2011). A leader should be in a position to provide feedback to the concerned people to avoid any mistake that is likely to occur in the course of management (Carter and Greer, 2013). Amanda should make his employees provide him with feedback concerning the nature of their duties and he should also provide them with feedback on how he manages the business. Management should clearly define goals of his team to ensure that they know what they are working to achieve and by what means and to enable them prioritize their workload. Recruitment process should be conducted in a slow but sure