In order to properly appreciate the importance of aluminum recycling in our world, an aluminum recycling experiment was done through alum synthesis. The process by which this was done recycled solid aluminum can pieces (Al) into the form of solid raw alum crystals (KAl(SO4)2) through a series of reactions. Application of this experiment comes from analyzing the calculated percent yield of alum crystals, understanding where error is involved, and determining how a perfect yield could be obtained. First, 0.9-1.2 grams of aluminum pieces were weighed out and placed in a 250 mL beaker, in which 50 mL of 1.4 M KOH solution was added and a fume hood was placed. The mixture was placed on a hot plate and stirred to speed up the reaction. Meanwhile, …show more content…
2KAl(OH)4 (aq) + H2SO4 (aq) → 2Al(OH)3 (s) + K2SO4 (aq) + 2H2O (l) In this acid-base/precipitate reaction, the sulfuric acid added to the potassium aluminum hydroxide formed aluminum hydroxide, the white, jello-consistency precipitate that was observed. Potassium sulfate and water were also formed. 3. 2Al(OH)3 (s) + 3H2SO4 (aq) → Al2(SO4)3 (aq) + 6H2O (l) Immediately after the precipitate was formed, the third, acid-base/metathesis reaction started. The solid aluminum hydroxide mixed with the sulfuric acid reforms into an aqueous aluminum sulfate in the water that was also formed. In this reaction, the aluminum sulfate created in the second reaction is being used up with the excess sulfuric acid in the third. This process was initiated as soon as the precipitate formed, but only time allowed for the formation of aluminum sulfate. Thus, the solution was heated up to speed up the reaction. Once this step was completed, the solution appeared smooth and clear again, representing the aqueous aluminum …show more content…
Al2(SO4)3 (aq) + K2SO4 (aq) + 24 H2O (l) → 2KAl(SO4)2 ∙ 12H2O (s) In this combination reaction, aluminum sulfate, potassium sulfate, and water were combined to form potassium aluminum sulfate, or the white, cornstarch-consistency alum crystals in water. It was this water that had to be filtered out of the alum crystals in order for them to dry and accurately record their mass. The theoretically yield for this experiment, based off of the mass of aluminum pieces originally weighed out, was 19.0144 g, while our actual yield was 12.7222 g. This is a 66.91% yield. Ideally, of course is a 100% yield. Factors that may have caused this in our own experiment include, but may not be limited to: 1) There was barely any hydrogen gas being produced in the first step when we took it off the heat, but enough to infer that the reaction may not have been completely over, possibly affecting the amount of potassium aluminum hydroxide produced 2) Having to filter the reaction mixture in the first step more than once, because we neglected to turn on the vacuum the first time, we may have lost some of the mixture in the process. 3) In the last step, when the solution was put in the ice bath, it was up to us when we thought enough crystals had been formed as to when to filter the crystals. Perhaps waiting longer would have produced more
Coursework Equipment List • Boiling tubes (8) I will use these because this is where I will mix both the sodium carbonate and the strontium nitrate in order to form the precipitate. I need 8 because I am going to add 8 different amounts of strontium nitrate (1-8cm³) to the 8cm³of sodium carbonate. • Measuring cylinder (1) I will use this to measure the 8cm³ of sodium carbonate and the varying amounts of strontium nitrate to put into the test tubes. • Sodium Carbonate (enough to fill 8 boiling tubes with 8cm³/64cm³)
Alka-Seltzer is a medical drug that works as a pain reliever and an antacid. The pain reliever used is aspirin and the antacid used is baking soda. When sodium bicarbonate dissolves in water it splits apart into sodium and bicarbonate ions. The bicarbonates reacts with hydrogen ions from citric acid to form carbon dioxide gas and water. This is how the bubbles are made.
In cycle one, the double displacement reaction, Cu(s) + 4HNO3(aq) → Cu(NO3)2(aq) + 2NO2(g) + 2H2O(l) occurred, the result of the reaction was that the reaction mixture began to bubble with the copper filling dissolving and a vapor like substance leaving the reaction. Furthermore, when water was added, the color change, from brown to a blue color pigment. Then in Cycle two, another double displacement reaction occurred, Cu(NO3)2(aq) + 2NaOH(aq) → Cu(OH)2(s) + 2NaNO3(aq), which resulted in the reaction becoming cloudy and a darker shade of blue. Following cycle two, a decomposition reaction occurred as the result of heat being administered to the mixture, thus the following reaction occurred in cycle three, Cu(OH)2(s) → CuO(s) + H2O(l). As a
Alka-seltzer is an easy pain killer. What makes an alka-seltzer dissolve? The formula for an alka-seltzer is 3HCO3−+3H+→3H2O+3CO2. This is what makes it dissolve. Sodium bicarbonate or baking ions react with hydrogen ions then mixes ions with water, carbon dioxide gas which is the fizz.
Malachite was synthesized using the following reaction (1): 2CuSO4*5H2O(aq) + 2Na2CO3(aq) CuCO3Cu(OH)2(s) + 2Na2SO4(aq) + CO2(g) + 9H2O(l) Based on this chemical equation, two moles of aqueous hydrated copper (II) sulfate reacted with aqueous sodium carbonate, a precipitate of copper (II) carbonate hydroxide was formed along with aqueous sodium sulfate, gaseous carbon dioxide, and liquid water. The copper (II) carbonate hydroxide precipitate is also the malachite that was obtained from the solution. It was known that a chemical reaction was occurring when the copper (II) sulfate solution was mixed in with the sodium carbonate based on the fact that the color of the solution changed from blue to light blue and the solution frothed. The malachite
In the round-bottom flask (100 mL), we placed p-aminobenzoic acid (1.2 g) and ethanol (12 mL). We swirled the mixture until the solid dissolved completely. We used Pasteur pipet to add concentrated sulfuric acid (1.0 mL) to the flask. We added boiling stone and assembled the reflux. Then, we did reflux for 75 minutes.
The powder on the filter paper could've fell and this caused it to have a smaller percent purity, percent yield and also cause a lower absorbance and concentration of pure ASA. Another error would be not using a properly dried sample for the pure ASA in part C when making the crystals, this could have cause tye percent yield error. This would make a lower melting point. To prevent this from occurring next time there could be a dry sample that is completely dry and this would not alter the mass of the sample and this would make the solution have a more
As seen in table 1, the theoretical yield was .712 g of C_17 H_19 NO_3. The % yield of this experiment was 7.51 % of C_17 H_19 NO_3. . This low yield can be explained from a poor recrystallization technique combined with potential contamination. Throughout the experiment, the mixture changed color from green, orange, to yellowish lime, and eventually clear.
Within the chemical reaction are two different parts, the reactant and product. The reactant, “an initial substance in a chemical reaction” was the alka-seltzer tablets, before they were placed into the water. For instance, when the untouched alka-seltzer was then placed into the water, it formed the product, “the final substance in the chemical reaction” (Tro, 2018). Now, by looking at how the water, or the solvent, dissolved the alka-seltzer tablet, it then created a solute, or a “dissolved substance” (Shuster, 2014). Another example, on a personal level, of a chemical reaction was, whenever I had a sore throat, as a child, my
+ H2O (g) Reaction 4: when a sulphuric acid is added to the solution that contains copper (II) oxide, a double displacement reaction will occur. the copper (II) oxide will react with the sulphuric acid producing copper (II) sulfate and water. The copper and hydrogen gas replace each other. Balanced Chemical Equation: CuO (s) + H2SO4 (aq) —> CuSO4 (aq) + H2O (l) Reaction 5: when zinc is added to the copper (II) sulfate solution, a single displacement reaction will occur.
There are only two circumstances in which I think the copper could have been lost. The first chance where some of the lost mass of copper may have gone could have been during the first reaction. If distilled water was added to the solution before the chemical reaction finished, some copper may have been lost during that step. While all nitrogen dioxide gas seemed to have dissipated, perhaps, it was not finished yet. By stopping the reaction early, all of the solid, elemental copper may have not had a chance to react with the nitric acid, and some mass may have been lost during the step.
Pertaining to the appearance of the oil and water before the reaction occurs, oil “sits” on top of the water because oil is less dense than water, and therefore rests on the surface of the water. The Alka-Seltzer, or effervescent tablet, reacts with the water and produces bubbles of carbon dioxide gas. This gas is less dense than both the water and oil, so it travels the the surface of the liquid, pulling a small amount of the colored water with it and creating the “lava lamp” effect. The chemical reaction that is occurring is an acid-base reaction, and results from the reaction between the ingredients in the Alka-Seltzer tablets.
As soon as the wire was submerged into the solution, the aluminum atoms and the copper (II) ions underwent a reduction-oxidation (redox) reaction, meaning aluminum was oxidized and donated its electrons to the copper ions, which were reduced. As a result, solid copper began to form on the surface of the aluminum wire, giving the wire a brown-orange color that resembled rust. The wire had to be regularly shaken in order to remove the solid copper particles and thereby expose more of the aluminum wire to react with the surrounding solution. As the reaction progressed, the liquid copper chloride solution slowly began to lose its color and turn clear. This was a chemical reaction, as seen by the bubbles formed with the wire was added, meaning gas was released when aluminum was oxidized and copper was reduced, but it also gave rise to physical changes, such as the change in color of the solution from blue-green to rusty orange to clear.
Aim: To find out the relationship between the greater concentration of sodium thiosulfate when mixed with hydrochloric acid and the time it takes for the reaction (the time it takes for the solution to turn cloudy) to take place and to show the effect on the rate of reaction when the concentration of one of the reactants change. Introduction: The theory of this experiment is that sodium thiosulfate and hydrochloric acid reach together to produce sulfur as one of its products. Sulfur is a yellow precipitate so, the solution will turn to yellow color while the reaction is occurring and it will continue until it will slowly turn completely opaque. The reaction of the experiment happens with this formula: “Na2 S2 O3 + HCL =