Determination Of Copper Sulphate Using Colorimetry Lab Report

Potential error could result in when quantitatively transferring in any step and spillinng or not transferring all of any given solution. When diluting each flask has a different level for where its specific volume is, so overfilling the flask is possible when not being focused on. The condition of each penny can impact the results by if some copper was chipped off, or if anything attached to the pennies could impact test results. All of these could result in a different than desired copper percentage. It is important that the absorbance of each penny be within the range of absorbance the calibration curve has. This is because the curve created for this lab was made with 0.00 – 10.00mL of Cu^(2+)stock solution when using those values idealy this curve should therefore be 0-100% copper percentage. If values were found outside of this calibration curve then there would be problems with either calculations or a different curve would be needed to properly record

Due to this fact, the concentration of copper in the solution is able to be calculated by using light absorbance. Since zinc doesn’t absorb any light, we are able to deduce that the greater the absorbance, the greater the concentration of copper.

Then 8.0g of copper sulfate crystals were placed inside the beaker and the mass was recorded for the actual crystals. 50 mL of water was added to the beaker with the crystals. The ring stand was set up with the wire mesh on it and one partner should place the mixture in the beaker on it should be heated without letting the mixture boil. Stir the mixture and heat until the crystals are dissolved. While one partner does this, the other should obtain 1.5g of iron filings in a measuring cup and records the mass. Then the iron filings should be added small amounts at a time to the heated solution. Stir continuously until all the mixture is added to the beaker. Then it sat for 10 minutes and observations were recorded. Record the mass of a filter paper and set up a filtration apparatus with the filter paper in a funnel over an Erlenmeyer flask. Decant the liquid through the paper slowly trying not to allow any solid to get on the filter paper. Then with de-ionized water, rinse your solid in the beaker and let the solid settle then decant the liquid. Repeat the washing twice more and in the last time guide all the solid into the filter paper. Then place the filter paper on a watch glass and then into a warm oven to dry. After it is cool, record the mass of the watch glass, filter paper and solid. If there is not enough time to cool, you may have to do it the next

Put approximately 9-10(g) copper ore into beaker. Use spatula to break up any large pieces. Next add 17ml H2SO4 (aq) (hydro sulfuric acid) to the beaker. Began mixing until all or most traces of blue dissipate; or the copper ore will no longer dissolve (should appear as a milky liquid). Next use pipette to and remove solution and divide solution into 2 individual test tubes then Place test tubes into centrifuge and run centrifuge for 1 minute. Remove from centrifuge machine Fill a cuvette with the clear solution from the test tube making sure not to disturb the sediment at the bottom. Note the solution should bluish in tint Final place the cuvette in the colorimeter. Then record data and calculate in results section.

Then in the last test tube fill it up with 5ml of sodium sulphate. Then after that carefully pour the sodium carbonate solution into the test tube labelled copper chloride solution examining the result and recording appropriately.

If it wasn’t constant then the time, intervals wouldn’t be equal. If the current is larger, there will be more electrons flowing around the circuit and more copper will be deposited.

Before the synthesis of the Copper Iodine Compound, the identities provided (CuNO3)2 and Nal weighed 1.65 g and 4.7 g, respectively. After being weighed, the (CuNO3)2 exhibited a blue color, while the Nal, through observation, was a white color. However, when both identities were combined, the product turned into a brown and red rocky material. Once 20 mL of deionized water was added, the product quickly turned pale pink paste. After the solution was repeatedly washed with a total of an additional 100 mL of deionized water, the product was powdery and pink with small grains, and was left to air-dry. Once the product was air dried, it was observed to be a pale pink color, while the filter paper was stiff as the product was hard and dry. Therefore, the solid was scraped off onto a recrystallizing dish. However, the mass of an empty recrystallizing dish needed to be recorded in order to compare how much of the synthesized copper iodide was obtained. Within this case, the empty recrystallizing dish used weighed 32.01 g, the product on the empty dish weighed 1.03 g, having a total weight of 33.04 g.

The lab performed required the use of quantitative and analytical analysis along with limiting reagent analysis. The reaction of Copper (II) Sulfate, CuSO4, mass of 7.0015g with 2.0095g Fe or iron powder produced a solid precipitate of copper while the solution remained the blue color. Through this the appropriate reaction had to be determined out of the two possibilities. Through the use of a vacuum filtration system the mass of Cu was found to be 2.1726g which meant that through limiting reagent analysis Fe was determined to be the limiting reagent and the chemical reaction was determined to be as following:-

Once all of the copper has reacted, the solution is diluted with distilled water, changing the solution from a dark brown to a pale blue color.

With this, the normal rate of absorbance could be measure and compared to those that contained chelating agents in order to see if the ion that was taken away by the chelating agent was needed. 5 mL of dH2O was added to Tube 5. Tube 5 was the calibration tube considering it contained nothing but distilled water. All of the substances were added to the tubes by pipettes in order to accurately measure the amount of substances. Whenever the chelating agents (the PTU, Citric Acid, and EDTA) were added to the tubes, the agents were taken from the top of the solution by a pipette in order to avoid the parts of the solution that had settled.

Determine how many grams of Copper Sulfate Pentahydrate you will need for your 100 mL of Water using the solubility curve. (See solubility curve)

Today, I finished my proposal for my EEI and started researching for calculations to predict the solubility of my solutes. My decided solutes are sugar, salt and copper sulphate pentahydrate. I decided I would be using 100mL of water as my solvent due to the abundance of solutes available and that fact that 100mL is a nice, easy number to work with. I also spoke to Mrs Rach and she informed me she has a surplus of copper sulphate so I don’t have to be careful with how much I use. She also gave me some measurements on how much copper sulphate should dissolve into 100mL of water at varying degrees. It’s a good start and I’m going to see if I can validate these measurements once I work out the prediction equations. I’m hoping to have my risk assessment handed in by the end of Friday’s lesson, but first I have to decide on how much of each solute I need. I will do further research during the week on solubility and the appropriate equations.

This laboratory exploration attempted to determine the LC50 of copper concentration and a mixture of copper, zinc, and manganese from the mine tailing leachate on Daphnia magna. Acute metal toxicity testing guidelines were followed and dose response curve was developed to determine these values. The LC50 of copper concentration was approximated to be 56 μg/L. The LC50 for the mine tailing leachate with the prevalence of Zn, Cu, and Mn metals was the dilution factor of 1:1.57. These values were compared to literature values. It was concluded that various environmental parameters, including pH and hardness have a great influence on metal toxicity.

0.5% of copper sulphate solution was added by drop at a time and and the test tube was shaked continuously.

12. The crocodile clips are attached to the copper electrodes of the experimental apparatus and the power supply is turned on. Simultaneously, the stopclock is started. The thermometer is checked every 30s. 13. After 300s the stopclock is stopped and the power supply is turned off. The negative cathode is carefully removed and is dried using a hair dryer. 14. When dry the negative cathode is placed on the electronic milligram balance and its final mass is recorded. 15. The positive anode and negative anode of the experimental apparatus are disposed and the electrolyte is poured out to ensure that the anode slime (impurities) does not contaminate the solution. 16. The electrodes of the experimental apparatus are replaced with new copper strips. 17. Steps 7 to 16 are repeated. However, this time, the rheostat is adjusted using the calibration apparatus until the multimeter shows approximate readings of 0.40 A, 0.60 A, 0.80 A and 1.00 A respectively. 18. Time permitting, the entire experiment is repeated. Safety Copper sulphate may cause irritation and burns if it comes into contact with the eyes. As standard lab procedure, safety goggles and lab coats must be worn at all times. Control of Variables Volume of Electrolyte Used