Copper Practical Essay Example

Copper Practical Essay Example Copper Practical Essay Copper Practical Essay In this practical I will be making copper. Copper is extracted by reduction although for many purposes such as electrical wiring, copper is required in a high state of purity. For this purpose, copper is purified by electrolysis. Purification of copper by electrolysis consists of an anode made of an impure copper plate and a cathode made of a pure copper plate. The electrolyte is copper (II) sulphate solution. All of the impurities that were in the impure copper plate are collected at the bottom of the cell and are known as anode mud. This can also be refined to produce precious metals such as silver, gold and platinum. Materials Bunsen burner Malachite powder (copper carbonate) Carbon powder Heat proof mat Weighing scales Beaker Test tube Filter paper Cold water Spatula Test tube rack Scrap paper (for using as a surface when weighing the malachite powder) Risk Assessment Risk Danger Precaution Action Malachite powder(copper carbonate) Harmful if swallowed. Powder and dust irritates lung and eyes Handle carefully making sure no powder falls If swallowed wash out mouth. If inhaled get fresh air Carbon powder Inhalation affects lungs Handle carefully making sure not to drop powder or inhale if inhaled get fresh air glassware Could break, causing wounds and bleeding Handle carefully and wear goggles at all times Inform teacher and clear away immediately Method 1. I put 2.5 grams of malachite powder into a large test tube and heated it gently, until it turned black and stopped rising in the test tube. 2. I allowed the test tube to cool. 3. I added 2.5 grams of carbon powder and mixed well. 4. I heated the mixture strongly until it turned red. 5. I let the mixture cool. 6. I then separated the copper from the waste by half filling put the copper onto the filter paper to dry it. I measured the test tube with water and poured the mixture into a beaker of cold water. 7. I then left for 2 minutes and then poured off the dirty water. 8. I kept adding cold water to the mixture and poured off the dirty water until I saw pink copper at the bottom of the tube. 9. I put the copper onto filter paper to dry it. I measured the mass of dried copper. This was my actual yield. 10. I calculated my percentage yield. Results Calculating percentage yield 2CuCO3 2CuO +2CO2 first heating it in air 2CuO+C 2Cu+CO2 heating with carbon Relative atomic masses Cu=63.5 C=12 0=16 Relative molecular mass of copper carbonate (CuCO3) = 248 Calculation= 63.5+12= (163) =123.5 Relative atomic mass of copper (Cu)=63.5 Actual mass of CuCO3 used= Theoretical mass of copper produced= 127 x 2.5 x 247 Percentage yield= actual yield Theoretical yield Conclusion In this practical I was successfully able to create some copper, using the correct laboratory method to create it. However, my copper is impure, with lots of unwanted substances within it. My copper also has poor electrical properties. However, copper which is made in industry also has the same problems, although industries fix this problem by us a variety of methods which I will explain later. Evaluation As my copper is impure, it would not be very suitable for use in industry. When copper is produced in industry, companies ensure they do everything possible to increase the purity of the copper. Purifying copper by electrolysis Copper can be purified by electrolysis. Electrolysis allows you to gain a higher percentage of pure copper as opposed to having impure copper. When aqueous copper sulphate solute is electrolysed on copper electrodes, the copper is deposited on the cathode (which contains pure copper) and the anode loses weight (the anode has the impure copper on it). The aqueous copper sulphate solution has copper ions (Cu2+) and sulphate ions ( SO42-). In the process of electrolysis, the positive Cu2+ are attracted to the negative cathode, which is where they have an increase in the number of electrons and also form neutral copper atoms. The copper is deposited on the cathode. The opposite also occurs in electrolysis. In electrolysis, sulphate ions are attracted towards the positive anode. However, these are ions are very stable and are not discharged. Copper atoms, which are what the anode is made up of, give up 2 electrons to form Cu2+ ions. This technique is carried out industrially to purify impure copper. In industrial electrolysis, the impure copper forms the anode of the electrical cell. The cathode is a sheet of pure copper. The el ectrolyte in this process is copper sulphate solution. The impure copper gets rid of the impurities and pure copper is deposited on the cathode. Electrolysis an important method if the purity of the copper is an important factor in the production process. However, electrolysis is an expensive method to carry out. Also, occasionally it can be difficult to separate pure copper from the carbon. Purer copper is produced in a short period of time, although in order to get a good yield it is necessary to leave the electrolysis to happen over a period of a few hours. Electrolysis works best and most efficiently when it is carried out without any pauses. Electrolysis should be carried out continuously without any pauses. Errors During my practical I encountered errors. I overcame these errors by following all the precautions required, which I will explain. My first possible source of error was when weighing the malachite powder. I could have weighed too much of the malachite powder without noticing and so this may have affected my final result. I overcame this by carefully weighing the malachite powder on accurate scales and zeroing the scales before I weighed the powder, so the weight of the malachite powder did not add onto another weight which would have made my results and practical inaccurate. My second possible source of error was when I was burning the copper until it turned red. I may have been burning the copper for too long and/or not noticed that the copper had already turned red. I overcame this error by concentrating and observing the copper carefully. My third possible source of error was when I was taking the copper out of the test tube and putting it onto the filter paper. I may have accidentally left some of the copper at the bottom of the test tube. This may have been because I had accidentally left it at the bottom of the test tube or I may not have been able to take the copper out of the test tube. I also may have lost some of the copper on my glass rod when I was stirring the solution. Industrial manufacture of copper In this section I will be comparing the method I have used to manufacture copper with the industrial method used to extract and manufacture copper. I will sow this in the form of a comparison table. Comparison point Industrial method( carried out in the blast furnace) Laboratory/school method Grinding the ore process In the blast furnace, this stage is carried out by utilising a crusher first to get individual pieces. These pieces are then grounded into smaller pieces in water by using steel balls in a rotating cylinder. In a laboratory, the copper ore (copper pyrites) is crushed up by using a mortar. It is then further crushed until it is a fine powder. Concentrating the ore The ore is then concentrated by getting rid of all unwanted impurities by carrying out the process of froth flotation. Flotation is the process of crushing impure rocks and then separating the ore from the impurities in order to gain the rich metals. It is used in industry often. In schools and laboratories where there is not access to froth flotation, the ore is concentrated by heating it. This converts it to copper oxide, which has a higher copper content within it, therefore making it more concentrated. Separating the copper This is process of several steps. 1) Matte is produced in a flash furnace. The dry ore is mixed with sand. The word equation of this reaction is as follows: CuFeS2+ 5O2+2SiO2 2Cu2S,FeS + 2FeSiO3+ 4SO2 2) The matte and lag are tapped off separately. Sulphur dioxide is used to create sulphuric acid. 3) Air and sand is reacted with matte. 4) The iron sulphide reacts with air and it is then converted into slag. The word equation to describe this is as follows: 2FeS+ 3O2+2SiO2 2FeSiO3+2SO2 (which is the slag) 5) The copper sulphide reacts to produce a copper metal. The word equation to describe this is as follows: CuS2+O2 2Cu+SO2 6) The end product from all of these stages is called blister copper. It is about 98% pure. The method used for this is the same as I have done in the practical. The copper oxide heated in a test tube with carbon, which produces impure copper. The word equation to describe this is as follows: 2CuO + 2Cu 2Cu + CO2 Purifying the copper To further increase the level of purity of the copper, electrolysis is used. 1) The copper metal is drawn into anodes and it is then electrolysed using 0.3 M copper sulphate 0.2 M sulphuric acid. To ensure you are only gaining pure copper, pure copper cathodes are used. 2) A reaction occurs at the cathode, which can be described as follows: Cu2+(aq) + 2e- Cu(s) This copper is now 99.99% pure. In the laboratory and school, the same level of accuracy does not occur when compared to industrial standards. 1) The copper and carbon mixture is mixed with water and then it is poured into a beaker. 2) This copper is then allowed time to settle. 3) After it has settled, the carbon and water mixture is poured away again. 4) This process is repeated several times. As you can see from this comparison table, the manufacture of copper in industry is a lot more precise and accurate than the manufacture of copper in the school or laboratory. In industry, all methods are employed to ensure that the copper is a pure as possible. However, in school, although every effort is made to try to remove all impurities, some impurities still remain as schools and laboratories sometimes do not have the equipment to ridden the impurities from the copper. In industry, there is key difference in the scale of production from the scale of production within a school or laboratory. In industry, copper is produced on a very large scale, as the copper is required by many people and as a result demand will be higher. This makes industries produce more copper. On the other hand, when copper is produced in the school or laboratory, it is only required by a few people and for small, limited use. As a result of this, there will not be much point in creating lots of copper, which is why copper is produced on a small scale in the school or laboratory. Another area where there is a difference between the industrial production of copper and copper production in the school or laboratory regards cost. Industrial production of copper is on a large-scale and therefore requires a lot more equipment and higher level equipment to maintain a high industrial standard. This requires the expenditure of a lot of money in order to buy the high level equipment. As a result, the cost of manufacturing copper in industry is a lot higher as opposed to the cost of manufacturing copper in school or the laboratory. The reason why the cost of producing copper in school is not very much is because low level equipment is used to manufacture it. In school, we only used basic equipment during our experiment. This equipment does not cost very much and therefore manufacturing copper in the school or laboratory is not expensive.