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

Hypothesis: some metal carbonates decompose more easily than others when they are heated.

Extracts from this document...

Introduction

´╗┐Thermal decomposition of carbonates Introduction: Carbonates decompose when they are heated, producing calcium oxide and carbon dioxide. Carbon dioxide can be detected using lime water. Calcium carbonate calcium oxide + carbon dioxide CaCO3 CaO + CO2 Other metal carbonates decompose in the same way. Here are the equations for the thermal decomposition of copper carbonate: copper carbonate copper oxide + carbon dioxide CuCO3 CuO + CO2 Hypothesis: some metal carbonates decompose more easily than others when they are heated. Aim: The times taken for a chemical reaction to take place metals high up in the reactivity series (such as calcium) have carbonates that take a lot of energy to decompose them. Metals low down in the reactivity series (such as copper) have carbonates that are easily composed. This is why copper carbonate is often used at school to show these reactions. It is easily decomposed and its colour change, from green copper carbonate to black copper oxide, it is easy to see. Risk Assessment Lime water Copper carbonate Spillages Bunsen burner Boiling tubes Hair General lab safety rules Can cause skin to go red or blistered. ...read more.

Middle

Heat the carbonates till lime water turns milky, keeping track of time. Lift the delivery tube from the limewater before the heating is stopped. This is to avoid suck-back. Write down all observations. Notice what happens to the limewater and how long it takes to turn milky. Notice whether any melting occurs in the heated test-tube and any colour changes taking place. Repeat the experiment with the other metal carbonates supplied, and in each case write down your observations. Carbonates Reaction Time Zinc Carbonate Turned yellow after a few seconds then turned black. Turned yellow Turned yellow 2 minutes 2 minutes 2 minutes Calcium Carbonate Lime water turned cloudy after a minute No change but gas is produced in the boiling tube No change 2 minutes 2 minutes 2 minutes Copper Carbonate Turned black Turned black Turned black 2 minutes 1 minutes 49 seconds 2 minutes Anomalies These are results that are abnormal and random. The anomalies on my results are circled. The reasons for these are a random or human error. ...read more.

Conclusion

The experiment was easy to set up but it was difficult to heat the carbonates the same way each time as the clamp was constantly moving whenever we removed the boiling tube but did not seem to affect the results as they were all accurate. Some of the powder did not reach the bottom of the boiling tube which means that it would not get heated as strongly and would take longer to decompose. The hypothesis taught me that some metal carbonates decompose more easily than others when heated. Equipment Measuring cylinder 3x boiling tubes 2x delivery tubes 1x spatula Teat pipette Bunsen burner Heat proof matt Stand Clamp Stopwatch Test tube rack Lime water Calcium Carbonate Copper Carbonate Zinc Carbonate For measuring limewater For putting metal carbonates in To carry carbon dioxide into lime water To transfer metal carbonates To transfer limewater safely To heat the metal carbonates To stop the surface burning To hold the clamp Attaches to the stand and holds the boiling tubes To measure two minute intervals To hold the test tubes To check for Carbon Dioxide To test the hypothesis To test the hypothesis To test the hypothesis ...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 Patterns of Behaviour section.

Found what you're looking for?

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

Here's what a teacher thought of this essay

3 star(s)

A reasonable write up which has a good beginning and method. It however loses momentum in the last section and does not give suggestions how the method could be improved. 3 Stars.

Marked by teacher Louise Star 21/06/2013

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 Patterns of Behaviour essays

  1. Marked by a teacher

    Chemistry copper sulphate and zinc

    3 star(s)

    From the lines of best fit (marked as 'linear' on the legend) we can see that one of my predictions was wrong. I predicted that the greater the amount of zinc, the faster the rate of reaction. This is untrue, as we can see from both graphs that the cup

  2. Rusting Lab. Hypothesis: I think that the presence of salt will speed up ...

    The graph shows a strong positive co-relation. The graph shows that the amount of rust almost increases in proportion to the amount of salt added to the test tube. This can be seen on all points on the graph except the one for the test tube with 0.4g of NaCl.

  1. Studying the reaction between zinc and copper (2) sulphate solution.

    The smallest temperature increase was just 9 whereas the largest increase was 24 that's a total range of 15 between the biggest and smallest results. Evaluating Evidence Overall I think the experiments were a complete success, I also think this is shown in the accurate set of results which have been obtained from the experiments.

  2. Determining the Enthalpy Change of the Decomposition of Calcium Carbonate.

    Results CaCo3 reacting with 2 mol dm-3 HCl. Attempt 1 Attempt 2 Attempt 3 Mass of CaCO3 + weighing bottle. (g) 6.4 6.27 6.48 Mass of empty weighing bottle. (g) 3.9 3.7 3.88 Mass of CaCO3 used. (g) 2.5 2.57 2.6 Initial temperature of acid. ((C) 18 19 19 Temperature of solution after mixing ((C)

  1. Factors Affecting the Rate of Catalytic Decomposition of Hydrogen Peroxide.

    Results taken directly from the graph: Concentration (mol) Rate of reaction (s) 0.4 0.0070 0.8 0.0145 These results confirm that the relationship is directly proportional according to my graph and line of best fit, as 0.8 is double 0.4 and 0.0145 is roughly double 0.0070 - i.e.

  2. Investigating the reaction between zinc and copper sulphate

    This should occur as zinc is higher in the reactivity series than copper. The reactivity series is as follows: Element Symbol Group Number Potassium K 1 Sodium Na 1 Lithium Li 1 Calcium Ca 2 Magnesium Mg 2 Aluminium Al 3 Carbon C 4 (Non-Metal)

  1. A-Level Investigation - Rates of Reaction – The Iodine Clock

    Potassium Iodide (0.1M and 1M), Sodium Thiosulphate (0.25M and 0.025M), Hydrogen Peroxide (2 and 20 volume) and Sulphuric Acid (0.1M and 1M) are all stored in biurets at the side of the lab. It is possible for the Potassium Iodide to 'go off' (iodide ions will oxidise to iodine in

  2. An Experiment to show the affect of Copper Sulphate Solution on Catalase.

    A decrease in either of these concentrations would result in a slower reaction. An inhibitor is a substrate which competes with the catalyst. It aims to deactivate the enzyme's active site. It achieves this by either deforming the structure of the enzyme (a non-competitive inhibitor)

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