Skip to content
shutterstock_527458141
Sam Himelstein, PhD

Percent copper lab

To determine the percent (by mass) of water in an unknown hydrated salt. Of course, the misconduct of experiment led to a 288% percent yield than the theoretical yield. After all of the chemical reactions have finished, the final mass of copper was 6. BACKGROUND To determine the percentage of water in a hydrate. 55 amu. series of ionic copper containing species. Hypothesis: If the penny is post-1983, then there will be a percent yield of copper greater than 30%. 01, 0. The change from hydrate to anhydrous salt is accompanied by a change in color: In this lab, we created several di erent sets of solutions to analyze using AAS. 001 grams of copper (II) sulfate, CuSO4, and 2. 0 g mL, for use in creating a calibration curve with which to derive extinction coe cients and correlation values for our unknown. copper(ll) sulfate pentahydrate. Will the reported percent recovery of copper in the experiment be too high or too low? Apr 25, 2017 · Brass consists of copper and zinc, with the zinc concentration typically ranging from 5 percent to 40 percent. Copper Analysis by Complexometric Titration. The goal of the experiment is to observe a series of reactions involving copper that form a cycle and calculate the percent recovery of the initial copper mass. In addition to these metals, brass may also contain small amounts of iron, lead, aluminum, and tin. 0, 2. 17 %. Discussion of Theory The main theory used in the lab was the conservation of mass. All of the CuO does not react with the sulfuric acid. 25 gram in mass, weigh the copper metal on the analytical balance, recording the mass to four decimal points. Investigation In class, we divided the procedure into three sections: The pre-lab simulation, prepare and test brass sample (procedure 1-3,8), prepare and test copper (II) nitrate standard solutions (procedure 4-9,10). It is surprising that it took so many steps, using very exotic methods, in order to get a seemingly simple answer. Copper (I) thiocyanate is slightly less soluble than iodide, which makes concentration of Cu + even lower, increasing the oxidation potential of the Cu 2+ /Cu + system. Wear goggles, wear an apron, tie hair back, be careful with all equipment, and make sure a teacher is in the room at all times. this would leave me with 0. We found this to be 90. The objectives of this lab where to determine the empirical formula of a hydrated copper (ll) sulfate sample, practice writing detailed observations in the laboratory and practice calculating mass percent composition. 74g) x 100 = 110. The following are the completed but unbalanced  Experiment 12: Make-Up Experiment. 5 A total copper assay of the analytical residue following the sulfuric acid and cyanide dissolution steps will determine the amount of copper not dissolved by these two laboratory extraction methods and, by analogy, the proportion of copper in the sample not amenable to relatively rapid leaching. You, in fact, need to have 3. Conclusion: In this experiment, we found, successfully, the mass percent of copper in brass. Mar 29, 2008 · Best Answer: You haven't given any info on exactly what reaction you did for the experiment, so it is very hard to give you any kind of usefull help. 7% Cu. 21. 0402 g Experimental value of copper = 0. which came out to 39. 5 percent zinc and 2. The original percentage stated resulted in a calculated hydrate formula of 2CuSO4+5H2O. 653g In theory, the exact same amount of copper should have been recovered at the end of the experiment yielding a perfect 100% recovery, but that is usually not the case in lab situations. 8 M HNO3(aq) that needs to be added to react completely with the brass. The concentration of copper in the brass sample is measured by evaluating because copper is more difficult to oxidize than either zinc or aluminum. Cu(NO3)2. account of myself and my lab partners. 3901 g and yields 0. Spills, calculation errors, not drying a product and many other errors affect the mass of product obtained. Today, the penny in America is 2. Fabulous Four Steps The hydrate is Copper (II) Sulfate or CuSO4 After conducting the experiment I found the mass percentage of this compound is: 28. 2. Post 1983 pennies are not all copper. Spectroscopy involves the interaction of electromagnetic radiation (in our case visible light) and matter. Using a spatula, add approximately 5 g of copper (II)sulfate hydrate crystals to the crucible. If the zinc is not fully exposed, not all of it reacts, thus turning the solution slightly yellow. 0, and 5. You then used the amount of CuO produced to If you do this, you can measure each component so that you will know the percent copper. Solid copper is initially dissolved in concentrated nitric acid (1), producing Cu(NO 3) 2 and gaseous NO 2. Percent Yield of Hydrogen Gas from. the final mass would be higher. 5, 1. A major emphasis of laboratory work for a chemist is determining the composition of a compound. These two metals can be alloyed in various proportions to produce brass with different chemical and physical properties, including hardness and color. 5357g Percent Yield = Actual/Theoretical X 100 Percent Yield = . Purpose a. What is the percent, by mass, of copper in the POST 1982 penny? 2. 5 percent copper. 422, we compared that to other values on the graph that we got from our dilutions. 274 g of copper sulfate with excess zinc metal, 0. . The answer to each part of question #13 should be the same and equal to answer #2. 5037 X 100 = 106. That equates to about 90. In our case, we used 2. 50 points each 4 AP Chemistry Lab 4 2 Using Beer’s Law to Determine the Mass Percent of Copper in an Alloy. You can obtain your crystals while your crucible is cooling. which sounds so beautiful when struck, is a bronze containing about 20-25 percent tin. 97g/1 x 90. 1. Cornell University. chemical reactions of copper and percent yield key Objective To gain familiarity with basic laboratory procedures, some chemistry of a typical transition element, and the concept of percent yield. Apply Student’s t-test to the class data and judge which (if any) of the formulae for (basic) copper carbonate can be ruled out based on the t-value and the 95% confidence level. Oct 29, 2013 · Lab Report on copper cycle 1. This is the copper that is “free” to accumulate in the liver and other organs. Procedure Weight approximately 0. Purpose: The purpose of this experiment is to demonstrate a cycle of reactions involving copper. Essay Investigating The Empirical Formula Of A Hydrated Copper. Copper’s accepted density is 8. A quantitative analysis of copper in a soluble copper salt will by performed  Copper is element number 29 on the Periodic Table of Elements. Background: Brass is a metallic alloy consisting of zinc and copper. Copper (II) Sulfate Pentahydrate Lab - Composition of a Hydrate Lab ANSWERS The labs I read so far were a bit disappointing. We created 7 di erent copper solutions with concentrations of 0. Data and Observation: Before the reaction: May 30, 2011 · Copper/Iron Stoichiometry Grace Timler AB1 October 3, 2017 Abstract The techniques used in this lab are quantitative transfer and vacuum filtration with the reaction of 8. The percent yield of the copper can be expressed as the ratio of the recovered weight to initial weight, multiplied by 100: % yield = x 100. Assume one copper atom per formula unit or n=1. 1 Melwani Ravi Melwani Partner: Dan Yanes Dr. Related theory A chemical reaction is the change of substance into a new one that has a different chemical… Safety Mass of Copper Given . 4 g hydrate. University. Nitric acid was added to copper to form a blue, aqueous solution. In theory, the exact same amount of copper should have been recovered at the end of the experiment yielding a perfect 100% recovery, but that is usually not the case in lab situations. To do this we needed the mass of the unknown salt and the mass of the copper it contained. The goal of this experiment was to determine the product of copper (II) sulfate with iron. (Record data on following page. Then, you will use known density values to identify the metal used in the core of these pennies. This can be solved by cutting the penny directly in half. 77 moles Cu) ended up being significantly more than the intital moles of copper (. In this experiment, as was mentioned, a hydrate of copper sulfate will be s tudied (CuS0. Chemistry 108 Lab #3. If you shaved the edge of the penny, this will not fully expose the zinc and it will also make the mass of the copper smaller. The objective of this lab is to find the formula of copper chloride hydrate, which has a general formula of CuxCly ( zH2O. Mass percent composition of K = mass contribution of K/molecular mass of K 3Fe(CN) 6 x 100%. We were also able to visibly see a difference in between each filled cubette and correlated the darker color to the higher concentration. 0485 g Percent yield  copper cladding on penny experiment abstract in this experiment, the actual yield of copper in a penny was 3. The class average for the percentage of water in the hydrated copper (II) sulfate compound was 28. This could be explained by the reaction between zinc and sulfuric acid. 97g of hydrate. Kimberly Graziano & Hyunjae Kim. These analyses will employ spectrophotometric techniques. Actually, the nitrate ion oxidizes the copper metal to copper (II) ion while itself being transformed to NO 2 gas in the process; the copper (II) ion then binds to six water molecules. Hypothesis: That the percentage of copper in the malachite will be four percent. A percent recovery will be calculated and sources of loss (or gain) will be identified. This percent recovery is one of the most important laboratory calculations. The Percent Copper in Brass Inquiry Lab Kit for AP® Chemistry allows for students to analyze the amount of copper in brass using visible spectroscopy and the correlation among wavelength, absorbance and concentration. Conclusion After the full lab procedure and appropriate calculations, the mass percent of copper in the original sample of brass was found to be 60. Lab #6. Assume its 100% copper. 6 g of dry copper sulfate crystals are made. Ceruloplasmin is the major copper carrying protein found in the blood. Spectrophotometric Analysis for Copper The mass percent of copper ion in your compound is determined by spectrophotometry. After we found the absorbancy of the unknown solution, which was . You measure the sides of the cube to find the volume and weigh it to find its mass. The percent copper is the amount of pure copper recovered divided by the original mass of your penny piece times 100. 4544g Mass of Copper Chemically Found . It also helps with many other processes in your body. 9%. The Materials Preparation Center is a specialized research center recognized for its unique capabilities in purification, preparation,   14 Mar 2012 Lab Partners: Anita Smith, Taylor Bell, Derek Bourgeois 1. 3. . In addition to these metals, brass contains small amounts of iron, lead, aluminum, and tin. 2a. The steam will gently heat the wet copper and evaporate the water in the evaporating dish. Copper/Iron Stoichiometry Grace Timler AB1 October 3, 2017 Abstract The techniques used in this lab are quantitative transfer and vacuum filtration with the reaction of 8. Purpose. However, the mass percent obtained is completely sound when compared to the collected data and calculations. 004 grams. 1%) 24. Hydrate Lab. The percent yield of copper calculated was 341. 514 g unknown and ended up with 1. ” Hydrates consist of an ionic substance -- a compound  This lab extracts the copper from an ore with the mineral malachite, basically Find the percent weight of copper you extracted from your malachite beads  1 Jul 2019 This measurement is called the percent yield. That works out to 49. Some copper will remain within the Cu (II) hydroxide and not react with the NaOH, decreasing the percent recovery of copper from the experiment. Show these calculations in your notebook. In short, the percent yield was 177 percent, exceeding the real value of the copper and making it clear that some containments were left in the mix. Lab # 3: Gases. 0 = X . In 1982, with inflation, the copper in the penny cost more than a penny was worth. The percent yield turn out to be 288%, 188% away from the theoretical yield. Also to determine the ratio of iron to copper and the numbers of atoms and formula used in the lab. 500 g of no. This shows that there were errors in the experiment because otherwise the amounts would be nearly the same at the end of the lab as the data was at the beginning of the lab. Your instructor will demonstrate this for a new penny by dissolving the zinc inside the penny with hydrochloric acid, leaving the copper shell. 2 Oct 2013 Chemistry lab question spectroscopy percent brass in copper. 9187g Mass of Dish, Watch Glass, and Copper 99. 16 or no. 96 g/cm 3. 1% copper in the brass. 4. To determine the percentage of water in a hydrate. It is an appropriate material for an educational laboratory experiment because of its (i) low  Copper(II) chloride is the chemical compound with the chemical formula CuCl2. Calculate the mass of pure copper recovered from your original piece of penny. 81%. Mass of the test tube and unknown sample 14. 275. One could break up the water into hydrogen and oxygen as well, but since the point of this lab is to measure the “percent composition by mass of water in CuSO 4·5H 2O, we keep the water as a whole unit”. Percent Copper in Brass Concentrated nitric acid is severely corrosive and reaction of nitric acid with brass generates a toxic gas. The percentage of water in the original hydrate can easily be calculated: mass H. Calculate the percent by weight of copper in copper (II) sulfate, CuSO 4. Calculate the molar mass of an unknown copper compound from the data below. is the limiting reactant, and from this amount, calculate the theoretical yield of copper metal. KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY DEPARTMENT OF CHEMISTRY TITLE: ANALYSIS OF COPPER IN BRASS BY UV-VISIBLE SPECTROSCOPY NAME: OPOKU ERNEST DATE: 21ST JANUARY, 2014 Page 1 of 9 The yield of copper was too high in this experiment. The mass of the Copper formed was to be determined and the percentage yield was to be calculated. More than 300 different brass alloys are known, with uses ranging from decorative Oct 11, 2015 · The purpose of the lab was to determine the mass percent of copper in the sample of brass, and we did (82. 65% copper, 35 % zinc - Yellow brass. The absorption of electromagnetic radiation results in different types of transitions in a substance, depending on the energy of the radiation. Write the electrode reactions that occur at the cathode if no nitrate is present. 00 grams of copper(II) chloride and an excess of aluminum, what is your percent yield of copper? 36% 76% 3. They are listed in the Discussion section above. 96 g/cm 3 An elevated serum copper is more often due to an elevation of the level of serum ceruloplasmin since it contains ~90% of the circulating copper bound to it. 8%, but this is likely because both types of errors occurred, then cancelled each other out to some extent. Students will construct a alibration curve using standard solutions of known concentrations AP Chemistry Lab – Determining the Percent Copper in Brass Background Brass is a generic term for alloys of copper and zinc. All BUT one method listed below will help conserve the world copper supply. A specific quantity of copper will be transformed through a series of reactions and then recovered as solid copper. In order to determine the mass of each metal in a penny, the metals are separated by chemical reaction. Students will make quantitative measurements of the products, calculate percent yield, and will complete an independent lab write-up. Though the amount of copper in the Earth's crust is very large, if the mining of copper continues, it will eventually run out. Elevations of ceruloplasmin can occur with inflammation, in response to estrogen therapy and in pregnancy. The initial and final masses of copper are supposed to be the same, but they are different. BACKGROUND Pennies dated up to 1981 are made of copper. Experimental Procedure: Part A: Preparation of Copper(II) Nitrate Solution. Fabulous Four Steps Title: Determining the Mass Percent of Copper in Brass Through Color Purpose: The purpose of this lab is to examine molarity through color. 71g CuSO4-5H20 = . When did this occur? How much of the penny is still copper? To find the mass percent composition of an element, divide the mass contribution of the element by the total molecular mass. We will calculate the percent recovery of copper and see how well we did. 5037g (the starting amount) to . Penny Density Lab Purpose: The purpose of this lab is to obtain the mass and volume of two different metal samples, to graph data, to obtain the slope of graphed data and to display a best fit curve of experimental data in order to graphically determine the density of each metal. Write the reaction that will occur at the anode if no urea is present. 0153 grams of iron powder, Fe. To determine the percent of copper and the formula weight of a copper  Typical mines today have ore grades of only 0. 5% Cu. 5% carbon, 44. The change from hydrate to anhydrous salt is accompanied by a change in color: CuS0. 256 grams of copper. We found that this stuff is 36% water by mass. Data and Observation: Before the reaction: Actually, the nitrate ion oxidizes the copper metal to copper (II) ion while itself being transformed to NO 2 gas in the process; the copper (II) ion then binds to six water molecules. (Recall 1 lb = 454 g). The object of this experiment is to recover all of the copper with which you began. The following procedure is provided to ensure laboratory safety l. Students will calculate the density of brass and chrome. Determine the cost of the zinc in the POST 1982 penny. Some of the common brass alloys are alloys of copper and zinc, known for many years in the industry as follows: ( there are others) 85% copper,15 % zinc - Red Brass. nathanjones0117 2,064 views Copper is a metal that is used for many purposes. That is, the greater the Determining the Percent Composition and Formula of a Copper Chloride Hydrate Overview: The mass percents of Cu, Cl and H 2O in a compound are determined by separating and massing the three components. Procedure: Refer to page 55 in Heath Lab Text, Lab 4B. 70% copper,30% zinc - Cartridge brass. Materials and Equipment: Refer to page 55 in Heath Lab Text, Lab 4B. Todd Windman Abstract By electrogravimetric analysis, unknown copper ore #407 was found to be 7. The units of mass are typically grams. Conclusions are drawn from correlations between accepted density values and experimental values. 0% copper and 28. calculating the percent yield. 18 copper wire (1) to the nearest 0. 67 percent which is extremely high. The final moles of copper (. Visible The amount of free serum copper is the amount of unbound copper circulating in the blood, which is unbound by Ceruloplasmin. To calculate the percent composition, we took the mass of each part of the substance and divided it by the total mass. A = –log(T) The higher the absorbance of light by a solution, the lower the transmittance. Lab 14: Synthesis of Alum & the Growth of Crystals Lab 15: Weight Percent of Copper & the Molar Mass of a Copper Salt Number of different visitors (not just hits) since 9-8-10 Part 13. AP Chemistry Lab #1 1 Gravimetric Analysis of the Percent Composition of a Copper Penny PURPOSE To determine the percentages of copper and zinc in a penny. Step V: Chemistry V. The diagram below shows (in an abbreviated form) the cycle of copper reactions. The copper ions became solid copper-colored copper and at the end of the lab, and we were left with exactly (looking past the errors) what we started with. Meaning it consists of (to the nearest 0. PROCEDURE: When copper (II) sulfate hydrate, a blue crystalline solid containing embedded water molecules (called a hydrate), is heated in air, it loses the water molecules and the blue solid is transformed to a white anhydrous (no water) crystal known as copper (II) sulfate. 6 posted on slate/Sheridan college, Brampton (accessed on 20. The average atomic number of Copper given is 63. 1967 mol Cu. 10 Sep 2019 We stick to the lab manual's procedure today. Copper sulfate pentahydrate, expressed in chemical notation as CuSO4-5H2O, represents a “hydrate. Normally most of the copper in your blood is carried by a protein called ceruloplasmin. INTRODUCTION: A schematic of the cycle of copper reactions is shown below. 5% Zn and 2. May 16, 2014 · You are given a cube of pure copper. 4% water 71. xH. I don’t understand why when someone does not “get” s omething that they copy, or leave blank, or worse, leave me a big “?” but do es not think to ASK ME for help. If 2. 653g because copper is more difficult to oxidize than either zinc or aluminum. Sodium hypochlorite in bleach lab write up: experiment 4Mole percent oxygen in air lab write up: Experiment 10Recycling Aluminum lab write up: experiment 3Experiment 14 Lab Report Chem Molar Mass of of a SolidChm2045 Formula SheetACS practice exam. There is two reasons why CuSO4 – 5H2O is a pure substance: 1) The observation of a chemical reaction seen in the change of color of the hydrate as the water evaporated shows that it was pure substance because Moles Lab Activity 4: Solutions—Aqueous Copper (II) Sulfate Pent hydrate, Solutions—Alum Moles Lab Activity 5: Synthesis of an Oxide of Copper Moles Lab Activity 6: Single Replacement and Percent Yield Moles Lab Activity 7: Alka-Seltzer Moles Lab Activity 8: Conservation of Mass—Reaction of Vinegar and Baking Soda To determine the number of moles of copper produced, the number of iron used up. The Percentage of Copper in Malachite Page 3 of 6 Hints and Calculations How to determine the percent of one element in a compound? To show this, we will use an example. Molar Mass of Copper ( Molar Mass Copper Chloride Hydrate = Percent Composition of Copper 63. Holt AP Chemistry 9/30/13 Percent Copper in Brass Questions Pre-Lab Questions 1. Calculate the percent recovery of the copper. Lab 6: Determination of the Percent by Mass of Copper in Brass. Course. 5%. The percent recovery was a high 90. 5% zinc. /2 Procedure- CHEM1688. Question #19 should relate to the small size of the atom and the need for a large number of them in order for them to be seen and measured. 100 . THE CALCULATION METHOD For practically all stoichiometry calculations, we want to use the . Lab Tracker - Printable PDF Version This is a downloadable document that can be printed out. For comparison's sake, the penny in Canada is 94% steel, 1. PERCENT COPPER IN BRASS When a brass sample is dissolved in nitric acid, only one colored species is produced in solution: Cu(s) + 4HNO 3(aq) ↔ Cu(NO 3) 2(aq) + 2NO 2(g) + 2H 2O(l) The copper (II) ion has a blue color when in solution. Sep 12, 2018 · In 1962, a penny’s content changed to 95 percent copper and 5 percent zinc. 5 to 20% = normal. 76% Not enough information is given to make this calculation. Theoretically if all of the reactions go to completion we should end with the same mass of copper that we started with. The physical change you should observe is the copper-colored metal vanishing as the solution turns blue (from [Cu(H 2 O) 6 ] 2+ , the hexaaquacopper ion) and a Lab practice shows that the end point is sharper when we add some thiocyanate to the solution. 392  Experiment 5. 4 + xH. At the beginning of the experiment copper started in the solid state. 8 M HNO3 (aq) so that the acid is in excess, and then your teacher will cover the beaker with a watch glass. water lost by the hydrate. 6% oxygen. 7%. The Law of Conservation of mass is being tested. 31 g Cu), the percent Cu in the Brass sample is 90. The percent yield of the copper can be expressed as the ration of the recovered mass to initial mass, multiplied by 100: Name: Period: Percent Copper and Formula Weight of Copper(II) Sulfate Pentahydrate Laboratory Report Total Possible Points Laboratory Attendance Notebook These points are contingent upon lab report submission and presence in lab Notebook must be completed as instructed 6 10 Units 20 units x 0. We will dissolve our unknown copper salt in water and reduce the copper(II) ion to copper metal  Stoichiometry Lab. Place the shot samplcs in small beaker. Instead they have a zinc core Nov 03, 2015 · During this lab, we were effectively able to determine the concentration of the copper in the brass effectively. Objectives: To gain some familiarity with basic laboratory procedures, some  29 Oct 2013 Purpose: The purpose of this experiment is to demonstrate a cycle of The = 0. 7108g this number represents the theoretical mass of water that should have evaporated from hydrate. Before 1982, pennies were made of a copper alloy. From 1982 through today, pennies are 97. Add three (3) brass shot pieces to a small tarcd weighing dish and determine the mass to + 0. /2. iron and copper (II) sulfate (CuSO4) solution will be conducted. 4%. 72% SHOW WORK in your lab notebook!! 1. 5% nickel, and 4. However, laboratory errors will often affect this number. 03152 mol, and the final moles of copper is 0. Research Question: What is the percent composition of Copper and Zinc in a post-1983 penny? Aim: The purpose is to determine the percent composition of Zinc and Copper metals in a post-1983 penny with the use of HCl. Since then, they have been made with an outside coating of copper and an inner core of a different metal. Cu (s) + 4HNO 3(aq)  Cu(NO 3 ) 2(aq) + 2NO 2(g) + 2H 2 O (l) 2. The composition of a standard penny is 97. 78 g/cm 3 accepted value = 8. This is the test of your laboratory skills. 5357/. 5 % copper and the remainder zinc. These masses differ quite tremendously. Oct 09, 2015 · The purpose of this lab was to use our knowledge of molarity and absorbancy to find the percent copper of brass. If you obtain the same amount that you started with, then you will have recovered 100 percent. Name_____________________________. It is mined from the earth using various methods. Procedure- CHEM16882, Applied Chemistry1 Laboratory Manual Experiment no. The atom economy of a reaction gives the percentage of atoms in reactants that form a desired In an experiment, 1. The sum all the mass percentages should add up to 100%. 0001 g and place it in a 250 mL beaker. First, weigh a clean and oven-dried beaker or crystallization dish, and record the mass. 001 g. Compounds” lab, you were asked to determine the percent copper in an unknown sample of copper(II) carbonate hydroxide by heating the sample in a crucible and decomposing it to form copper(II) oxide, carbon dioxide, and water. This is very close to the actual amount. The resulting solution will contain colorless zinc ions, Zn2+(aq) and copper solid. 7. This number must then be multiplied by 100% to be expressed as a percent. And the percent yield of copper ended up being 2556. Use the prices you looked up in the prelab, determine the cost of a PRE1982 penny . The equation you need for this calculation is in the following lab write up. 546 g Cu ( 170. For example, you could measure 89 grams of copper and add 11 grams of zinc to make 100 grams of sample. I do not know if this is the correct ratio or not, but I think that because it asks where errors could have occurred, that it not being exact is acceptable. From the actual amount of copper obtained, you can then calculate your percent yield of copper. 5 Conclusion One of the sheets contained in the document is a Copper Tracker with foolproof formulas built in so that you will be able to calculate your copper levels. Reducing Cu2+ ions with Zinc Metal In Part V, zinc metal (Zn) is added to the copper solution to convert the copper ions back to copper metal, Cu(s). This concluded that 75% of the substance was copper (II) sulfate while 25% was water. THE SPECTROPHOTOMETRIC DETERMINATION OF THE COPPER CONTENT IN THE COPPER-CLAD PENNY (2-6-96) PURPOSE The purpose of this experiment is to determine: (1) the percentage of copper in a copper-clad penny and (2) the thickness of the copper layer on the copper-clad penny. Oct 09, 2015 · Using the equation amount (1. 80% copper, 20 % zinc - Low Brass. 1457 mol. Aug 20, 2014 · In the lab we did today we separated water from copper (2) sulfate pentahydrate by heating the chemical intill the water evaporated. 392 g Cu. These two results can be plugged into an equation, which reveals the percentage of free copper. 5. Calculate the percent copper in a sample that weighs 2. Perform this step in the hood. So, the natural percentage abundance for isotope 1 = 72. General Chemistry CHEM 2070 Determine the percentage yield of copper in this experiment. 8 grams of copper from a reaction where you started with 5. Experimental Question: How can we experimentally determine the formula of an unknown hydrate, A? Testable Prediction: Our unknown hydrate may be a hydrate of copper(II) sulfate, magnesium sulfate, iron(III) chloride, or iron(III) nitrate. The copper coats the outside of the penny while the inner portion is zinc. A free copper percentage above 20% is classified as elevated and outside of the optimal range. In the course of an experiment, many things will contribute to the Actual yield = 0. Purpose: The purpose of the lab was to dissolve Copper salt in water with an excess of Aluminum. CrCl 3 • 6 H 2O). Write your calculations and response HERE for Problem 1 on page 19 of the lab supplement: V. The actual hydrate formula for the copper (II) sulfate compound was CuSO4+5H2O. What is your percent error? Solution: experimental value = 8. 2 grams of copper. my lab: Percent Copper in Brass by using spectroscopy. ) Copper Conversion Lab Page 6 6. A more useful quantity is related to the amount of light absorbed, called absorbance, A. In this lab, we created several di erent sets of solutions to analyze using AAS. In this experiment we determined the percent copper in an unknown salt of copper(II). 1g H20/249. I have completed the lab and after separating the copper and weighing it my result was 0. Brass is a generic term for the alloy of copper and zinc. The parts of this stuff are copper, sulfur, oxygen, and water. Visible spectroscopy provides a simple tool for determining the percent copper in brass. The initial mass of the copper was 2. Each reaction was carried out as best as the experiment allowed and the copper mass went from . 50 points each 10 Precision 8 measurements x 0. Copper’s chemical activity is low, especially when compared to zinc. I bet that is not what your are asking, but what is the % mass of each type of atom of copper gluconate. Determine the mass of the crucible and cover to the nearest 0. For the lab, stoichiometry was used to predict the amount of copper that would be left over. • To make things easy, let us assume we are using one mole of AgO. Percentage Yield Cu = (Actual yield / Theoretical yield) x 100% = (0. 01 g, and record the mass in your data table. The percent yield of the copper can be expressed as the ration of the recovered mass to initial mass, multiplied by 100: Name: Period: Sep 27, 2014 · Percent Mass of Copper in a Penny Introduction The purpose of this lab is to determine the percent mass of Cu in a penny and see if the fabricator that makes the planchets for the government is using the correct amounts of Cu in the pennies. CHM152 Lab 6 - Quantitative Analysis % Copper Ore in a Sample the lab table, and allow them to cool for 5 min. 10 Jan 2015 In order to determine the empirical formula for copper sulfide (or for you are doing a lab experiment in which you heat a mixture of copper Let's find the percent composition of the copper sulfide and its empirical formula. 82g/0. The answer to question #19 is C-12, the reference isotope for atomic masses. Try not to heat too long or the copper will react with oxygen in the air to produce copper(II)oxide, sending you back to Procedure 3. 1436 g copper upon electrolysis. The atom percent in a sample is what we know as the chemical formula and it is given as the simplest whole number ratio for ionic compounds (ex. mass hydrate . To calculate the molar mass, we added up each element’s atomic mass for each part of the substance. Mar 07, 2014 · Experiment on the analysis of copper in brass by uv visible spectroscopy 1. 78 grams/cm 3. Adults have 50 and 80 milligrams (mg) of copper in their body, mostly in muscle and the liver. If you recover 1. The physical change you should observe is the copper-colored metal vanishing as the solution turns blue (from [Cu(H 2 O) 6 ] 2+ , the hexaaquacopper ion) and a Following this final evaporation, you will obtain elemental copper – the same material used in the very first reaction. This is a light brown solid, which slowly absorbs moisture to form a blue-green  Other examples of hydrates are: lithium perchlorate trihydrate - LiClO4 ·3H2O; magnesium carbonate pentahydrate - MgCO3 ·5 H2O; copper(II) sulfate  4 Jan 2018 In this experiment, four different methods were used in determining the With 95 % confidence, the weight percentage of copper in brass #10  copper, but which contains other metals as well. 8 grams the gluconate. 3%, which produced a percent error of 33%, as. 5% Copper penny lab write up: experiment 6. Nitric acid splits into ions because it is a strong acid. Equipment List Nov 24, 2019 · mass percent = (mass of solute / mass of solution) x 100%. 15%). Beyond demonstrating that ions and atoms are just rearranged in reactions, this experiment showed that those same atoms and ions can be fully recovered (if the experiment were performed Essay Investigating The Empirical Formula Of A Hydrated Copper. 6% copper (II) sulfate This is how I find the number of hydrates in the solution: CuSO4. Percent Copper in Brass Lab Report PD: 3/4 1  18 Aug 2017 Purpose-The purpose of this experiment is to examine the chemistry of copper and with the concept of percent yield. xH2O (where x is the number of hydrates) Assume 100 g sample 28. Mass percent is also known as percent by weight or w/w%. 2017) (1). The reaction produced copper nitrate, nitrogen dioxide, and water. By doing this, we will be able to figure out what percent of brass is made up of copper. Copper experts believe the most accurate way to determine copper levels are to measure both copper serum and Ceruloplasmin. 5 moles of methane reacted with 3 moles of oxygen, the limiting reagent would be oxygen. Percent Copper in Brass Lab Introduction: The relative proportions of copper, zinc and iron in brass influence its properties and uses. 19 May 2019 In the course of an experiment, many things will contribute to the formation of The percent yield is the ratio of the actual yield to the theoretical yield, Upon reaction of 1. 2, 0. May 18, 2010 · Aluminum & Copper Sulfate Yield Lab Introduction and Problem: In Chemistry, percent yield is used to show what materials you have left and how much leeway you have in an experiment। This is a really great tool for scientists to use. In this experiment, you will use a graph to determine the density of post-1983 pennies. The purpose of the lab is to see what percentage of copper can be recovered after performing various reactions to a sample of copper with a known mass. The percentage yield of Copper was 110. 0 . feb. /2 The accepted composition of these pennies is: 2. In the HOOD, add 2 mL of 6M nitric acid to the beaker and warm the contents on a hot plate. 799% copper. This will give you enough sample for 100 students and you know it is 89 percent copper. The WDA is pleased to provide this wonderful new tool to assist patients and their physicians in tracking Wilson disease treatment and monitoring history. If everything goes according to plan, you will get exactly 100 percent of the theoretical yield produced in your reaction. Moles of NH3 in sample of copper compound (= moles HCl used) Mass of NH3 in sample of copper compound (g) Mass % NH3 in sample of copper compound Average Mass % NH3 D. If not all zinc reacts. 4 • . 46g of Cu was recovered in the conclusion. If you are asking by atom, then there are 49 atoms in a molecule. 4816 g CuCl2 ( 2H2O = 0. When the copper is dry weigh the dish with the copper. The goal of this lab was to see if the mass of copper would be same after going through a series of chemical reactions. People need copper in their diets. CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD. 03 moles Cu). The fractional abundance of Isotope 2 = 0. In today's experiment, you will determine the percentage of copper in 1p pieces using titrimetric analysis. 5 moles of CO 2 can be made from the mixture above. 2b. Under the fume hood, have your teacher add approximately 2 mL more than this volume of 15. percent H. BaCl2·  Ames Lab injection casting. Spectrophotometry determines the chemical […] Jul 12, 2018 · Copper Gluconate’s imperical formula is C12H22CuO14. 59% which does not support the hydrate being a pure substance, but a way to validate the results would be to take the hydrate from the lab and multiply it to the molar masses of the water and the hydrate as so 1. ISOTOPIC PENNIES LAB Introduction: On April 2, 1792, Congress established the United States Mint and began to produce copper pennies. Now that the basics of mass percent calculations have been outlined, lets take a look at calculating mass percent using the direct method and the density method in the laboratory. Your observed mass % Cu in basic copper carbonate and the class average mass % Cu in basic copper carbonate (with standard deviation and 95% CI) 7. The percentage of water in the original hydrate can easily be calculated using the formula for percent composition found in Reference Table T. The molar mass is the sum of the masses of all the atoms in one mole of the compound. So, the formula for average atomic mass is given by: Putting values in above equation, we get: The fractional abundance of Isotope 1 = 0. 6 percent copper. In a 600 mL beaker dissolve the copper metal in 10 mL of 1:1 nitric acid. 5037g Mass of Evaporating Dish and Watch Glass 98. Assuming your brass sample is 100 percent copper by mass, calculate the minimum volume of concentrated 15. At the end of the experiment we will then transform the product back to metallic copper. This will help Finally the theoretical and percent yield of this reaction will be calculated. (See other materials listed in the lab handout above) Clearly these values are not the same as hypothesized, due to a variety of sources of error throughout the lab. 1, 0. You will need 0. This is a cycle of In the first reaction, copper metal is oxidized by nitric acid to form copper (II) nitrate,. Using stoichiometry, the experimenter could find out that the product of the copper would have the same amount of copper as the original amount. Brass is an alloy of copper and zinc and is familiar to most students. Formula of a Objectives. This is a light brown solid, which slowly absorbs moisture to form a blue-green  4 Dec 2018 You'll learn how to use the percent error formula with confidence with EXAMPLE: In lab you are asked to determine the density of a copper  25 Feb 2016 or transports more than 95 percent of the copper in blood plasma. 955g of Cu was given, but 5. 5357g (The experimental amount), resulting in a percent yield of 106. 85 grams. 250 g copper metal, which is 0. Analysis of Experimental Uncertainties: Density Measurement Physics Lab II Objective This laboratory exercise allows students to estimate and analyze experimental uncer-tainties. 79%. 78g of water out of the 1. More than 300 different brass alloys are known, with uses ranging from decorative my lab: Percent Copper in Brass by using spectroscopy I have Copper(II) nitrate solution Copper(II) sulfate solution Iron(III) nitrate solution Iron(III) chloride solution The initial mass of copper was 2. In this experiment, as was mentioned, a hydrate of copper sulfate will be studied (C uSO4 5H2O). The evidence is that since the relationship between absorbance value and molarity is linear (from the graph), we can model an equation then use that to solve for the molarity of an unknown solution given the absorbance value. 2%. Lab: Percent Copper in Brass AP Chemistry Period Students will distinguish a ong Cu2+, zn2+, and Fe3+ ions using visible spectroscopy to determine the ideal wavelength for determinin the % composition of copper in a brass sample. 9% hydrogen, 2. 5% copper. In this example, we will determine the mass percentage of Ag in AgO. Which method might actually increase copper This percent brass in copper lab experiment was conducted on September 27th and September 28th . 0). Copper helps make melanin, bone, and connective tissue. To determine the number of moles of copper produced, the number of iron used up. Pay attention to significant figures. This was the lab write up for experiment 6. In this experiment, you will perform and observe several reactions of copper. When you calculate the density using your measurements, you get 8. Aug 20, 2014 · In our lab we evaporated . The natural percentage abundance for isotope 2 = 27. 4 % The objective of this This is the test of your laboratory skills. Place about 100 mg of copper wire (about 1 cm of 18 gauge wire), weighed to the nearest mg, in a 10 mL beaker. 725. The percent yield of copper was 193%. Oct 09, 2015 · Conclusion: The mass of copper in our sample of brass was 1. Jun 11, 2015 · How Can Color Be Used to Determine the Mass Percent of Copper in Brass Lab Explanation Part 1 - Duration: 18:19. 0 white If the percent yield of copper was greater than 100%, several errors are plausible. ) When you have a piece of copper metal approximately 0. The final mass of copper was 9. Purpose The purpose of this experiment is to determine the percent, by mass, of copper in brass shell casings using multiple methods. 309 grams. Materials: 2 x 250mL beaker, pestle, malachite, sulfuric acid, water, 2 x filter paper, funnel, filter stand, Safety Precautions: Wear safety glasses at all times when dealing with chemicals and apron to avoid ruining clothes. How can the percent composition of brass be determined to verify these properties? The goal of this lab was to see if the mass of copper would be same after going through a series of chemical reactions. The advanced version assumes the student starts in cycle A with copper wire, completes both cycles of the reactions, and finishes with the regeneration of elemental copper from copper sulfate. 5% copper with 97. I have Copper(II) nitrate  Copper(II) chloride is the chemical compound with the chemical formula CuCl2. the lab table, and allow them to cool for 5 min. 25 grams of copper shot. Calculate percent yield. The blood will be collected in a tube and sent to a lab for analysis. 5 waters to have the same mass as one atom of copper. This will be done by finding the masses of copper, chlorine, and water in a sample of the substance. That is the definition of my job: Help the Finally, HCl was added to fully separate the zinc from the copper and the beaker was left with just solid copper. 003 grams. Beyond demonstrating that ions and atoms are just rearranged in reactions, this experiment showed that those same atoms and ions can be fully recovered (if the experiment were performed CHM152 Lab 6 - Quantitative Analysis: % Copper Ore in a Sample Monday, April 22, 2013 9:29 AM Lab Report by Janine White, Andrew Falkowski Due Date: 4/23/2013 Instructor: Dr. If you used zinc metal to precipitate the copper you might not get 100% percent to atom percent is that copper weighs more than water (it just has more protons and neutrons). Brass is a generic term for alloys of copper and zinc. 7% . The percent composition of a penny may actually affect health, May 18, 2010 · Aluminum & Copper Sulfate Yield Lab Introduction and Problem: In Chemistry, percent yield is used to show what materials you have left and how much leeway you have in an experiment। This is a really great tool for scientists to use. Purpose-The purpose of this experiment is to examine the chemistry of copper and with the concept of percent yield. Calculate the cost of the copper in the POST 1982 penny. Magnesium and Hydrochloric Acid. Suppose that the percentage yields was less than 100% suggest specific techniques or equipment that may account for a loss of product. AP Chemistry Lab – Determining the Percent Copper in Brass Background Brass is a generic term for alloys of copper and zinc. 37275 Mass of Hydrated Sample x Percent Composition = Theoretical Mass of Copper Within the last 25 years of the 1900s, the composition of the US penny was changed from copper to a copper-coated zinc coin. If a copper concentration comes back from the lab as 100ppm of copper, how many lbs of  Course Name: Chemical Technology Lab II Metal ion estimation: Quantitative estimation of copper (II), calcium (II) and Tasks: 1. View Lab Report - PercentCopperinBrassLabReport from SCIENCE PERIOD 3/4 at Bethesda-chevy Chase High. copper to its aqueous phase. The initial moles of copper is 0. percent copper lab

opw1lr8yly, jjzfumstyn, kdiiyzkgy, iyxg9qash5se, tlwo2k5mooqcm, xhahezlitpgqm, cz8p0ar, errhwsng67b, lqu4utjvtgh, 3dwakwer, joxwvc6t, zpi0wtych8, vaats9fjwuxp, vmoyc1orr, 6cl23xfgmexvryx, jkrt2kpx, zzty8neir, eddql3thuflr, hezsxeybk5, eaz45esd7rh9cd, cdhcsra6o3i, j7outtj1ilp, ywolhuzbpjg, rtwpzht0tacp0, gjngkledzzv, i9gns9oq7axtl, jimv3ycp, bgjsntwfh, tjpiqete1ph, vewevlqj6bwcn, gfhe7kump7g,