Need to improvement for this Lab Writ up Report Firstly, go to section 2,4 and 5 and read carefully red color feedback. Section: 2 Hypothesis a. Need to write a Hypothesis that will be first Hypothesis based on the Experiment, procedure & result. Section: 4 Analysis/Calculations: You have to write the formula of the precipitate based on the calculated molar ratio. Section: 5 Discussions and Conclusion: Which section will be appropriate for placing the formula of the precipitate? Lab write-up on Experiment-4 1. Aim: The aim of this experiment was to determine the formula of an insoluble salt formed by reacting an aqueous solution of copper (II) ions with an aqueous solution of iodide ions 2. Hypothesi a. What is the proof that copper iodide is formed when copper ions and iodide ions are combined? That should be included in your first hypothesis. You should also include another hypothesis that addresses the formula of precipitate b. It was hypothesized that the reaction between copper (II) ions and iodide ions would result in the formation of either copper (1) iodide or copper (II) iodide, depending on the interaction between copper (II) sulfate pently deate (CuSO. SHO) and potassium iodide (KD) in the reaction environment 3.Data Results/Observations: Results Mass of CuSO4-5H20 Mass of filer paper Mass of precipitate filter paper Mass of precipitate Analysis Calculations: 1. Mass of CuSO-SH:0=2.50g 2. Mass of Cu in precipitate Mass of precipitate+ filter paper-Mass of filter paper 3.578- 1.50g-2.078 3. Mass of I in precipitate-Mass of precipitate filter paper-Mass of Cu in precipitate 3.578-2.07g-1.50g Molar ratio of Cu and I: Mass of Cu-2.07g Melar mass of Cu63.55 gel Mas of 1-1.50 Molar Mass of 1-126.90 ol 2.50 1.50 3.57 2.07 To determine the moles of each element: Moles of Cu-Mass of Cu/Molar mass of Cu -2.07 g/63.55 g mol -0.0320 mol Moles of I-Moles of 1/Molar mass of -1.50 g/126.90 g/mol -0.0115 mol To determine the molar ratio of Cu and I: is the verdict? Based on the calculated molar ratio, what is the formula of the precipitate. Molar ratio of Cu to I-Moles of Cu/Moles of I =0.0326 mol/0.0118 mol = 2.76 5.Discussions and Conclusion: The hypothesis suggested the possible formation of either copper (1) iodide or copper (II) iodide based on the chemical environment of copper within the reaction. The result of the experiment indicated that the formation of copper (1) iodide, Cul, you included the formula of the precipitate. Just make sure that you mention the rationale why you think it's Cul under section 4, Calculations. was more likely due to the observed mass of Cu and I in the precipitate. An analysis revealed a mass ratio of approximately 2.07g Cu to 1.50g I in the precipitate. From this ratio, the molar ratio of Cu to I was calculated using the molar masses of copper and iodine. The resulting molar ratio, approximately 2.76:1, suggested that the formula of the insoluble salt formed was Cul. The formation of Cul implied the reduction of Copper (II) ions to copper (I) ions during the reaction. This process highlighted the dynamic nature of chemical reactions and the importance of understanding the electron transfer states of elements involved. In conclusion, the experiment successfully determined the formula of the insoluble salt formed by reacting copper (II) ions with iodide ions as Cul. This provided valuable insights into the chemical behavior of copper ions and the nature of electron transfer reactions in aqueous solution EXPERIMENT 4 FORMULA OF AN INSOLUBLE SALT INTRODUCTION One of the postulates of John Dalton's atomic theory states that compound substances consist of a combination of atoms of different elements in constant whole-number ratios. This has been incorporated into the law of constant composition which states that a compound always contains the same elements in the same proportion by mass. Thus if we know the masses of two elements that react to form a compound and we know the atomic weights, we can determine the formula of the compound In this experiment, an aqueous solution of copper(II) ions will be reacted with an aqueous solution of iodide ions to form an insoluble salt. The product of the reaction might be copper(II) iodide, Cul, since Cu and I have been reacted or the product might be copper(I) iodide, Cul. The iodide ion is a good reducing agent and might be able to reduce copper(II) to copper(I), resulting in the formation of Cul. A known mass of copper(II) sulfate pentahydrate, CuSO4-SH₂O, will be weighed to give a known mass of copper. This is reacted with an unknown amount of potassium iodide (KI) solution to form a precipitate which is collected and weighed. From the mass of the precipitate and the mass of the copper present in the precipitate, the mass of iodide that reacted can be obtained by difference. The reaction to form the precipitate is one of the following. Cu³(aq) + 21 (ag) → Cul:(s) 2Cu³(aq) +41-(ag) → 2Cul(s)+1(1) If the reaction forms Cul, iodine will also form and will contaminate the product. The KI reagent to be used contains sodium thiosulfate (Na:S:O) which will reduce any elemental iodine to iodide ion according to the following equation. I:(s) + 25:0;¹-(ag) → 21-(ag) +S40₂²-(ag) It is important to add just the right amount of the KI-Na-S₂O, solution. If too little is added, some copper(II) will remain in solution because it has not reacted. If too much is added, some of the copper (either I or II) will form soluble complexes and dissolve. The point at which the addition is to be stopped is readily determined by the observation of a color change which occurs when the correct amount has been added. PROCEDURE 1. Weigh a 2.50-g sample of copper(II) sulfate pentahydrate, CuSO, SH₂O, into a 250-ml. beaker and dissolve it in 70 mL of deionised water. 2. With stirring, add about 5 mL of 2.5 M KI-2.5 M Na:S:O solution to the CuSO4 solution. Then add more dropwise and continue to stir during the addition. When the brownish precipitate turns to creamy pale violet or pale yellow, stop the addition. The total amount of solution added will be about 8 mL. 3. Weigh a piece of filter paper. Place the filter paper in a filter funnel. Filter the solution into a 250-ml. conical flask, being certain to transfer all the precipitate to the filter paper (Figure 1). Use your wash bottle to wash the precipitate from the beaker into the filter paper (Figure 2). Wash the precipitate with another 10 to 15 mL of deionised water after all of it has been transferred. Figure 1. The correct method of decanting into the filter paper. Figure 2. Using a stream of deionised water from a wash bottle to transfer all of the solid into the filter paper. 4. Carefully remove the filter paper from the funnel and place it in a 250-ml beaker. (Caution: Since the filter paper is wet, it will tear easily.) Also, do not spill the precipitate from the filter paper. Leave the precipitate and filter paper to dry until the next laboratory session, at which time, weigh the precipitate and filter paper.