Then 5mL of HCl was added to copper to completely remove all traces of zinc. Once the bubbling had stopped, the rest of the liquid was decanted away from the copper. Then the copper recovery set up was put together using tubing, Buchner funnel, filter paper and suction flask. Then the filter paper was weighed before placing it in the funnel and wetted down. The aspirator was turned to medium high, and then the copper was poured onto wetted filter paper.
Pour all the filtrate and washings into a 250cm3 volumetric flask. Make up to 250cm3 with 1.0mol dm-3 sulphuric acid(VI) acid. Stopper the flask and invert several times to thoroughly mix the solution. 5. Fill the burette with 0.005mol dm-3 potassium manganate(VII) solution.
To perform this experiment, we will utilize emission spectra, titrations, and thermal gravimetric analysis, using knowledge from Experiments 10, 4, Titrations of Na2CO3 and NAHCO3 by HCl (hydrochloric acid) will be performed to determine the concentration of HCl, as well as the number of moles of HCl present within the sample of baking soda. As a result, we will be able to determine the molar concentration of HCl by determining its equivalence point (the point on the graph where the exact amount of rectant needed to perform a reaction has been added) from graphical analysis. Na2CO3(aq.) + HCl(aq.) ==> NaHCO3(aq.)
This reaction is carried out by adding a solution of reactant hydrochloric acid from a burette to a solution of sodium hydroxide until just sufficient of hydrochloric acid has been added to react with all of the sodium hydroxide. If the concentration and volume of hydrochloric acid is known the number of moles of sodium hydroxide can be calculated, if the equation for the reaction is known. This procedure is known as a titration and the point at which sufficient volume of hydrochloric acid has been added to the sodium hydroxide to complete the reaction is called the end point. An indicator which changes colour at the equivalence point is often used to indicate the titration end point. This standardized solution of sodium hydroxide can then be used to determine the concentration of acid in the sample of gastric juice.
Gravimetric Determination of Sulfate Purpose The purpose of this lab is to determine the percentage of sulfate in the hydrate by precipitating the sulfate as barium sulfate. Materials Filler paper Sodium sulfate Graduated cylinder Bunsen burner Watch glass Beakers (250 mL, 400 mL) Rubber bulb Graduated pipette Beaker tongs Funnel Filter Paper Sodium Sulfate Drying oven Wash bottle Stirring rod Silver nitrate Hydrochloric acid Distilled water Small test tube Procedures First, .4861 grams of sodium sulfate was placed into a clean 400mL beaker. Exactly 200mL of water and 1mL of HCl was added to the same beaker. A watch glass was placed on the beaker and the solution was heated using the Bunsen burner to a gentle boil. The watch glass was removed with the beaker tongs.
Three drops of phenolphthalein indicator was added into the HCl solution. The stopcock was opened and the NaOH solution was added into the HCl solution. The flask was swirled to mix the solutions and titrate to a faint pink end point. Recorded the final volume on the butret and used the final volume as a beginning volume to repeat the titration. At the second titration, the experiment was exactly the same as the first titration but the H2SO4 solution was used to instead of the HCl solution.
The pipette was then filled with 25.0mL’s of acetic acid and then drained into a conical flask, to speed up the process both of the conical flasks were filled with 25.0mL of the acetic acid. 8. Three drops of phenolphthalein was then added to the flask with the acetic acid. 9. The conical flask was then positioned to just under the burettes dropper which had its stopcock opened to allow a medium drip rate and had the sheet of filter paper slipped under it so that the colour could be seen more earily.
Then by writing a balanced chemical equation and using the titration formula, Nb+Ma+Va=Na+MbVb , the molarity is able to be determined. Procedure: 1) Using the graduated cylinder add 10.0 mL of water into the Erlenmeyer flask. 2) Add 5.0 mL of HCl into the flask using another graduated cylinder because acid goes into water when mixing them. 3) Add three drops of phenolphthalein indicator into the flask. 4) Swirl the flask in circular movements to mix the substances.