Determination of Cu2+ by Titration
Introduction:
The purpose of this lab is to determine the concentration of copper ions in an unknown solution. Complexometric titration will be used to determine the concentration. A buret will be used to deliver the complexing agent to the unknown solution. Ethylenediaminetetraacetic acid will be used as the complexing reagent. An indicator, Murexide in our case, will be used to indicate the endpoint of the reaction.
Theories and Concepts:
The anion of the acid, EDTA4-, will complex to the metal. This anion reacts with the metal by forming coordinate-covalent bonds with the metal. This is a coordination compound. This ligand is called a chelate because it can form coordinate-covalent bonds by wrapping itself around the metal. A total of six coordinate covalent bonds are formed between the copper cation and the ligand. The Murexide indicator will mix with the blue copper solution to form a compound that is purple. As soon as an exact amount of the ligand is titrated and binded to all of the metal in the solution the color of the soluti...
The purpose of the Unknown White Compound Lab was to identify the unknown compound by performing several experiments. Conducting a solubility test, flame test, pH paper test, ion test, pH probe test, conductivity probe test, and synthesizing the compound will accurately identified the unknown compound. In order to narrow down the possible compounds, the solubility test was used to determine that the compound was soluble in water. Next, the flame test was used to compare the unknown compound to other known compounds such as potassium chloride, sodium chloride, and calcium carbonate. The flame test concluded that the cation in the unknown compound was potassium. Following, pH paper was used to determine the compound to be neutral and slightly
We were assigned a group and instructed to measure the amount of different ions in that particular fertilizer sample by counting to preform tests. We used the formula SO4 + Agent —> Percipitat + others. Our job was to add 0.25 g of a fertilizer sample to 100 mL of water to dissolve, then add the agent Pb(NO2)3 to the water also, then filter and dry the water, and distinguish the mass. The was accomplished by using the % formula Mass SO4 = Mass Pb(NO3)2 x MW Pb(NO3)2/ MWPb(NO3)2 to gain the percentage, the the formula Mass SO4/MW SO4 =
Put 1mL of 0.1M cobalt (II) chloride hexahydrate dissolved in 95% ethanol into a test tube. Then add 1mL of deionized water. Tap the end of the test tube to mix the solution and record the pertinent data in section 2 of the Data Table. Discard the solution in the appropriate container as directed to you by your lab instructor.
In this case, the nitrate ion moved from one compound to another as the Cu was replaced by Zn. The zinc dissolved to form zinc (II) ions as the copper (II) ions came out of the solution as copper metal and deposited on the surface of the
When given a test tube of the unknown sample, four drops of 6 M HCl(aq) was first added in order to precipitate the ions into their respective chlorides, AgCl(s), Hg2Cl2(s), PbCl2(s), if present. After adding the HCl(aq) to the sample, the solution would turned milky white and a white precipitate settled to the bottom of the test tube, indicating that there was at least one of the ions initially present in the unknown solution. A large amount of HCl was not added because the AgCl(s) and PbCl2(s) would otherwise form soluble chloro complexes with the excess chloride atoms: PbCl42-(aq) and AgCl2-(aq). The solution was then centrifuged to fully separate the suspended chlorides from the liquid. An additional drop of HCl was then added to the
Although the majority of the copper remained within the beaker, some of the copper went along with the supernatant liquid that was removed. Since some copper molecules were inadvertently removed from the beaker, the overall weight of the copper later measured less than what it should have been. Another laboratory error was how zinc was not fully extracted from the solution. While taking out the zinc that was used to separate the copper ion from the chlorine ion, some residue could have been left behind. As a direct result of stirring around the solid zinc to knock off the copper, some zinc from the original piece broke off. Not knowing how much zinc was left behind likely caused the weight of the later measured copper to be greater than what it should have been. Overall, the weight variation of the copper sample, after the procedure, was not 100% accurate since it gain weight from zinc and loss some weight due to
are left in the solution, the more time there is for the copper to be
The aim of this investigation was to determine how five different metals of differing reactivity reacting with Copper Sulfate solution would affect the enthalpy change of the reaction.
The relationship between the mass of malachite used and the amount of copper oxide obtained was proportional. Malachite and calamine are next to each other in the
of Copper Sulphate. To do this I plan to work out the amount of water
The Electrolysis of Copper Sulphate Aim Analyse and evaluate the quantity of Copper (Cu) metal deposited during the electrolysis of Copper Sulphate solution (CuSo4) using Copper electrodes, when certain variables were changed. Results Voltage across Concentration of solution electrode 0.5M 1.0M 2.0M 2 5.0 10.6 19.5 4 10.5 19.8 40.3 6 14.3 26.0 60.2 8 15.2 40.4 80.3 10 15.0 40.2 99.6 12 15.1 40.0 117.0 Analysing/Conclusion The input variables in this experiment are; concentration of the solution and the voltage across the electrodes. The outcome is the amount of copper gained (measured in grams) at the electrodes. By analyzing the graph, we can see the rapid increase of weight gained for the 2.0 molar concentration as the gradient is steeper.
A titration is used to determine the amount of acid in a given solution. This is done by titrating a measured volume of acid (in this instance, acetic acid (CH3COOH)) with a solution of a strong base (usually sodium hydroxide (NaOH)), of a known concentration. The NaOH is added in small aliquots until the acid has been neutralised, and this can be determined with an indicator dye, such as phenolphthalein, or a pH meter (Nelson & Cox, 2008 pg58). In this practical, a pH meter was used and this allows for the acidity or alkalinity of a solution to be measured, and this was more accurate than using an indicator dye. The use of the pH meter in titration is generally preferred more over the visual indicator because the equivalence point can be measured
== § Test tubes X 11 § 0.10 molar dm -3 Copper (II) Sulphate solution § distilled water § egg albumen from 3 eggs. § Syringe X 12 § colorimeter § tripod § 100ml beaker § Bunsen burner § test tube holder § safety glasses § gloves § test tube pen § test tube method = == = =
In this experiment we are trying to identify an unknown acid or base and its concentration by using the method of titration. The pKa values and the titration curve help aid in identifying of the unknown. In our case we had a base as our unknown (analyte). The use of a certain amount of sodium hydroxide and hydrochloric acid will be used to titrate the unknown solution that is given. This is the tirant. We used hydrochloric acid as our titrant. We achieved a pH of 5.56 at an end point of 10 milliliters. The unknown’s concentration was around 0.098 M at pka(s) of 6 and 7. The sodium hydroxide and hydrochloric acid are called titrant and it is contained in a container called burette. The unknown solution is held in an erlenmeyer flask. The purpose of the experiment is to measure the weak acid and base by neutrilizing it and determining the unknown acid by titration.
Volume's Effect on a Copper Sulphate Solution We are trying to find out if the current though a copper sulphate solutions volume is increased. To find this information out I shall perform an experiment using the following equipment; · 1 power pack · 1 beaker · 2 carbon rods for anode and cathode · 1 ammeter · 1 measuring cylinder · 2 crocodile clip wirers I shall also be using 60cm3 volume of copper sulphate in my preliminary results to decide upon the concentration of copper sulphate and the voltage I shall use. The following diagrams show the step by step process in which I will do my experiment; [IMAGE] [IMAGE] [IMAGE] [IMAGE] I will take 10 readings from 10cm3 to 100cm3. I will repeat my experiment to give my experiment a fair average. I will keep the power pack the beaker the carbon rods the crocodile clips the ammeter the concentration of copper sulphate and the measuring cylinder the same each time I do the experiment this experiment.