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= (16x3) =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 electrolyte 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.
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.
Bibliography
http://www.chs.edu.sg/~limth/lessons/2002/Electrolysis/electrorefining_of_%20copper.jpg- this is an educational website which has online lessons on it. It is written by qualified teachers.
‘Science for GCSE’- written by Graham Hill (Hodder and Stoughton). This is a textbook used in my school during science lessons. It is written by a qualified and reliable author. As it is school textbook material, it is highly unlikely that the book will be giving wrong or inaccurate information. Therefore, it makes this source reliable for use in coursework.