• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Thermal Decomposition of copper carbonate

Extracts from this document...


Thermal Decomposition of copper carbonate Aim: Copper has two oxides, Cu2O, and CuO. Copper carbonate, CuCO3 decomposes on heating to form one of these oxides and an equation can be written for each possible reaction Equation 1: 2CuCO3 (s) ? Cu2O (s) + 2CO2 (g) + 1/2 O2 (g) Equation 2: CuCO3 (s) ? CuO (s) + CO2 (g) The aim of this experiment is to prove which equation is correct. This can be done by volumetric analysis i.e. calculating the volume of gas produced. This is then compared to the calculated volume of gas produced in each equation and the equation with the nearest volume of gas is correct. This is a thermal decomposition reaction and when an element like copper can form two oxides, which one forms is based on the stability of the compound formed. The more stable the compound, the more likely it is to form. The stability of a compound with respect to its elements can be predicted by the ?Hf (molar heat of formation). This is the energy change when 1 mole of a compound is formed from its elements. If it is exothermic (negative), then the compound is stable with respect to its elements. If it is endothermic (positive), then the compound is unstable with respect to its elements. In general, the lower the value of ?Hf, the greater the energetic stability of the compound with respect to its elements. ...read more.


For a compound the mass of one mole is the same as the relative formula mass or molecular mass in grams. The molecular or formula mass of a compound is found by adding the relative atomic masses of its constituent elements, as found in the periodic table. Substance Mr/Ar - and hence, mass of 1 mole (g) Copper Carbonate (CuCO3) 123.5 Copper Oxide (Cu2O) 143 Copper Oxide (CuO) 79.5 Carbon Dioxide (CO2) 44 Oxygen (O2) 32 So using the equation of a reaction, it is possible to predict the masses of products that will be made by a given mass of reactants. In this experiment, from the two equations given, it is possible to calculate how much gas would be given off by each. Avogadro's law states that 1 mole of any gas occupies 24dm3 at room temperature and pressure (rtp), so it is possible to calculate the volume of gas given off. The experiment can then be carried out, and the volume of gas produced compared with the predictions for each equation. Whichever equation best predicts the volume given off is therefore shown to be the correct one. Firstly I must deduce the amount of gases produced if 10g of copper carbonate is produced. No. of moles = Mass s Relative Molecular Mass Relative Molecular mass of Copper Carbonate = Relative atomic mass of: Cu (63.5) + C (12) ...read more.


This also guarantees that the results obtained are accurate 4. Light Bunsen burner and place under tube. 5. Wait until the copper carbonate has completely decomposed. This will be indicated by a color change, and the fact that the copper carbonate would have stopped bubbling. Copper carbonate is a green solid. Copper oxide is a jet black solid. Green Black 6. When you are sure the copper carbonate has completely decomposed, measure and note down the volume of gas obtained 7. Repeat stages 1 - 6 three to four times, and then take the average. This reduces the risk of error in your results. Also ensure that all variables capable of influencing the results are kept constant. For example, the same amount of copper carbonate is used in each experiment and using the same apparatus again helps reduce the risk of error Results Table 1 Measurement of boat Measurement of boat and Copper Carbonate Measurement of boat after Final measurement Table 2 Measurement of copper carbonate used g Volume of Gases produced cm� In this experiment if the volume produced is nearer to 242.9 cm� then It will mean that equation 1 is correct. If the volume of gases produced is nearer to 194.4 cm� then equation 2 is correct. I predict that the most probable equation that is correct is equation 2. Previous knowledge may also help to support this prediction as when anything combusts oxygen gas is never given off as a product because the oxygen is needed for the reaction. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Classifying Materials section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Classifying Materials essays

  1. Calcium carbonate reacts with dilute hydrochloric acid according to the equation below

    Increasing the concentration increases the pressure, making the molecules more 'squashed up' together; this means there is going to be more collisions. As the concentration of hydrochloric acid is increased, the rate of reaction increases. Therefore, the rate of reaction is proportional to the concentration of acid.

  2. Thermal decomposition of Copper Carbonate (CuCo3).

    No of moles of O2 = X dm3 at 25C and 1 atm pressure Molar mass of O2 = 32g Mass of O2 = no of moles of O2 X 32g =...g Mass

  1. Investigating the Factors Affecting the Temperature Change Between Zinc and Copper Sulphate

    The temperature difference I calculated for this mass was 6.7�C. Although this is lower than the next temperature of 6.85�C for 0.7g, there is not a large enough difference between the two for them to make sense. From my graph I can see that ideally the temperature difference for 0.5g should have been 3.25�C.

  2. Making magnisium carbonate (MgCO3)

    USES OF MgCO3 The MgCO3 is a stomach anti-acid and is present in various laxatives. It can be used as a base in the treatment of dyspepsia, gout and other diseases. In dentistry, MgCO3 is used in the gypsum impressions from which dental plates are made.

  1. Free essay

    Periodic table

    change during the lifespan to carry out a particular function. Some cells even die during this process. Examples include cells that make bone in mammals or those that carry water from the roots in plants. Viruses dead or alive? Viruses do not have an organelle nor do they carry out processes common to cells that are alive.

  2. Investigate a factor that effects the change in temperature between iron and copper sulphate.

    When observing the reactions I noticed that the copper sulphate had turned completely colourless when I added 3.2 grams of iron, showing that all the copper had been reacted with. Evaluation I think the method I used was fairly appropriate as I was able to gain fairly accurate results showing

  1. Investigating the thermal decomposition of Zinc Carbonate.

    After this I will weigh each test tube once again to get their new masses. From this I will work out how much zinc carbonate is in each test tube, I can do this by taking the mass of the empty

  2. Our experiment consisted of two samples of water containing unknown substances, and our objective ...

    Results and calculations Sample A Total volume of sample A = 256cm3 Volume of the sample of sample A used = 20cm3 * Mass of empty evaporating basin = 55.63g * Mass of empty evaporating basin + sample = 75.43g Mass of sample = ?

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work