Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  • Level: GCSE
  • Subject: Science
  • Document length: 852 words

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. Peer reviewed

    Rates of Reaction

    5 star(s)

    Digital Scales METHOD: 1. Firstly, get 3 large boiling tubes and place them in a test tube rack. 2. Measure 1 gram of calcium carbonate using the digital scales (in small pieces), and place it in a boiling tube.

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

    Timing Error: 1 The maximum time error = x 100 Smallest time measured Which equals approximately 1/20 x100 = 5% These errors seem surprisingly large, but in reality it will never really deviate this much since many of the times were well over a minute.

  1. 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.

  2. How Does the Changing Temperature Affect the Rate of Fermentation by Yeast.

    In my prediction I thought that the rate of reaction would be slow at 20?C and increasing at 30?C - the class results and my conclusion show that this is correct. In my prediction I thought that above 40?C the reaction would slow down again - but this was shown

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

    18 19 19 Temperature of solution after mixing ((C) 20 20 21 Change in temperature during the reaction. ((C) + 2 + 1 + 2 Average change in temperature ((C) 1.66 CaO reacting with 2 mol dm-3 hydrochloric acid. Attempt 1 Attempt 2 Attempt 3 Mass of CaO + weighing bottle.

  2. ICT modelling spreadsheet - This coursework was designed to investigate the uses of electricity ...

    Then add these two totals together add on the V.A.T., and a quarter of the standard charge onto this, giving you the final bill for the economy 7 tariff. The similarity between these two tariffs is that both are charged to the customer quarterly.

  1. Analyse and determine whether or not the concentration of glucose effects the time for ...

    molecule to react with each other to turn clear. Preliminary Work As preliminary work I did a dry run of my experiment The reason for doing this preliminary work was to find any faults before I did the actual experiment, this way I could make adjustments to overcome these problems and also I could find out suitable concentration intervals.

  2. Investigate the rate of a catalysed reaction, when altering the temperature of the solution ...

    3.75 5 6.25 7.5 8.75 10 To make my solutions, I used the burette to measure and fill a test tube with the starch, and used a pipette filler to measure the water. To this I added a drop of iodine and the solution went blue/black, this indicates that there is starch present in the solution.

  • Over 180,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work

Marked by a teacher

This essay has been marked by one of our great teachers. You can read the full teachers notes when you download the essay.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review on the essay page.

Peer reviewed

This essay has been reviewed by one of our specialist student essay reviewing squad. Read the full review under the essay preview on this page.