The limiting reagent in this lab was iron. Iron was the obvious limiting reactant because the 4.00 grams of iron was used to determine that 11.43 grams of copper sulfate would be necessary in the equation. Also, an extra 25% of copper sulfate was added to make sure there was enough copper sulfate in the reaction since it was the excess in the reaction. The theoretical yield of the reaction was 4.551 grams of copper. The theoretical yield is an amount predicted by stoichiometry and assumes that the limiting react is used completely; the yield was determined through stoichiometry by converting the amount of iron into the amount of copper in the reaction. The actual yield of the reaction was 4.411 grams of copper and was obtained through the experiment
An error that could have been present during the lab includes not letting the zinc react completely with the chloride ions by removing the penny too early from the solution. For instance, the percent error of this lab was 45.6%, which was determined by the subtraction of the theoretical percent of Cu 2.5% and the experimental percent of Cu 3.64% and dividing by the theoretical percent of Cu 2.5%. This experiment showed how reactants react with one another in a solution to drive a chemical reaction and the products that result from the
This shows that some impurities are present in the final product. Similarly, the experimental percent yield of 120.2% shows that some issues arose during the procedure. It is impossible to produce a pure product with over 100% yield; therefore, other impurities were present in the product that added weight to the finial mass. This extra weight pushed the yield well over 100%. This source of error could be due to a lack of drying the final product.
(2-3 sentences) First, percent yield cannot be over 100% because mass cannot be created; the collected mass of a substance can never go over the theoretical yield of that substance. Percent yield is also very rarely 100% because no equilibrium reaction, which is the type of reaction studied in this lab, can go to completion. There is always some amount of products that transforms back into reactants; therefore, theoretical yield, which assumes that the reaction goes to completion, will rarely equal experimental yield. 3.
Purpose: To recognize the evidence of a chemical change and to prove the law of conservation of mass by observing a series of chemical reactions involving copper. A specific quantity of copper will be transformed through a series of chemical reactions to form new substances and then recovered as solid copper. A percent yield will be calculated to determine the amount of copper recovered from the chemical reactions.
Be ready to discuss your claim with the class, and to write down the correct products for the decomposition of CuSO4●5H2O. Answer:_________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Claim Evidence Reasoning
In beaker with the formed CuSO4 from Reaction 4, a piece of aluminum wire, which was bent into a circular shape, was placed in the beaker, and completely submerged in the solution. To this beaker a small stir bar was added along with 5 drops of 6 M HCl to start the reaction. This beaker was place onto the hot plate, covered with a watch glass, and the stir setting on the hot plate was turned on so that the stir bar moved the piece of aluminum wire around and hit it repeatedly. The wire began to have copper form on it and the stir bar hitting the wire would knock off the formed copper. Before the beginning of the next step the reaction had to be completed.
*2H2O. The total molar mass in this equations is 434.05 grams. The percent yield of iron salt using the actual yield of 8.71 grams with a theoretical yield of 17.8 grams is 49%. Discussion:
In this lab, the hypothesis, if a chemical reaction occurs, there will be signs of a chemical change such as a change in temperature, color, and/or smell, was accepted. In each experiment, clear signs of a chemical reaction were observed. In chemical reaction #1, we put drops of vinegar onto a small pile of baking soda. The baking soda and vinegar produced bubbles of gas right as the first drop hit the baking soda, which is a clear sign that there was a chemical change occurring. This can be classified as a double replacement chemical reaction.
The purpose of this experiment was to prepare an unknown Grignard reagent and then identify the product by molecular weight and melting point. An IR reading was taken to further identify and validate what product was formed. DISCUSSION AND CONCLUSION Organometallic compounds consist of a carbon that is attached to a metal. The carbon atoms are strongly nucleophilic because of a partial negative charge that they carry.
The purpose of this lab will be to identify the percent yield of copper in the unbalanced equation _Al(s) + _CuCl2(aq) → _Cu(s) + _AlCl3(aq). This will be determined by cutting a piece of aluminium 9cm by 9cm, recording its mass in grams, preparing a copper (II) chloride solution using the weight tray and electronic scale to measure 5.0g of CuC12 and adding it to 100 mL of distilled water. Then, a stirring rod will be used to dissolve the piece of aluminium into the CuCl2 solution until it is no longer visible. Additionally, the mixture will be filtered using a filter paper (which was previously weighted) on a funnel and weighted after it is fully filtered. Furthermore, the chemical equation will be balanced, stoichiometry will be used to find
+ 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.
Stoichiometry of a Precipitation Reaction University Student Name Abstract The purpose of this experiment is to calculate the actual yield of Calcium carbonate from the reaction of Calcium Chloride with Sodium carbonate. We have to then compare the actual results with the theoretical value of Calcium carbonate and find out the error. When we mix 1.0 grams of Calcium Chloride and 0.80 g of sodium carbonate, it produces around 0.60 g calcium carbonate in the actual experiment.
This equation will provide for the ability to calculate the moles of both the given and desired substances, which can be divided to find the theoretical yield. An experiment will then take place: first, it is important to properly clean a working station and to wear goggles and a lab coat. A beaker can then be filled with 10 mL of of water before gathering 2 g of solid copper (II) sulfate pentahydrate, 2 mL of 6 molar hydrochloric acid, and approximately .25 g of aluminum foil as provided; a scale can be used to keep these measurements accurate. Using a stirring rod, stir the hydrochloric acid into the water before placing the solid copper (II) sulfate pentahydrate into the beaker of water. Let the hydrochloric acid and solid copper (II) sit in the water for two minutes as the next portion of the experiment is prepared.
The copper(II) metal complex was prepared by reacting copper(II) chloride and sodium saccharinate together by applying heat. The copper(II) chloride was originally a white solid and the sodium saccharinate was a blue solid. A centigram balance was used to weigh out a 1.01g sample of the sodium saccharinate and a 0.75g sample of the metal salt, copper(II) chloride. Each reactant was placed in separate 50-mL beakers and then dissolved using 10 to 20-mL of deionized water. Once dissolved the reactants were combined into a 250-mL beaker along with a clean stir bar.
Discussion 1) A balanced chemical reaction: Zn + CuSO4 ZnSO4 + Cu A full ionic reaction: Zn0(s) + Cu2+(aq) + SO42-(aq) Zn2+(aq) + SO42-(aq)