• 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...


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.


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.


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)

    These are: 1) Temperature increases the number of collisions When the temperature is increased the particles all move quicker. If they're moving quicker, they're going to have more collisions. Temperature: in a cold reaction mixture the particles are moving quite slowly. This means that the particles will collide with each other less often,

  2. The aim of the investigation is to examine the kinetics involved in the reactions ...

    A graph to show the distribution of energy: Ref: Nuffield Advanced Chemistry Students Book, Longman, p257. The graph shows the number of particles in each range of kinetic energy. The area beneath the curve is directly proportional to the total number of particles.

  1. A series of experiments involving the enzyme Catalase has been performed in order to ...

    31.67 Experiment 4 - The effect of inhibitors Concentration of Copper (II) Sulphate Solution (Moll��) Volume of Oxygen Produced in 60 Seconds (cm�) Experiment A Experiment B Experiment C Average Result 0 5.5 6 5.5 5.67 0.25 5 6 5 5.33 0.5 4.5 4 4 4.17 0.75 3 4.5 3.5

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

    Although these results appear to be perfect they cannot be completely reliable as they were not performed under exact conditions which it would need to be for them to be perfect. All of the zinc which we used was premeasured which meant that it was not completley accurate as it

  1. What affects a person's reaction time?

    Also we only when we did out preliminary experiment we only did the experiment 5times. This didn't give us a good range of results and caused the whole experiment to weaken. We noticed no adequate conclusion could be backed up with sufficient evidence as a suitable graph could not be formed.

  2. Rate of Reaction Lab Report

    Controlled Variable How was it controlled? Type of Acid Use Hydrochloric Acid (HCl) for the experiment Volume of Acid Set a certain volume of HCl: 20ml in our experiment Volume of Sodium Thiosulphate Solution Set a certain volume: 20ml in our experiment Concentration of Sodium Thiosulpate Solution Set a certain

  1. Disappearing cross (aka Rate of reaction).

    Both of the cylinders will be washed out and so will the conical flask before starting the next experiment, encase of contamination of a different liquid heated in the cylinders. The liquids will be heated at different temperatures; they are 200C, 300C, 400C, 500C and 600C.

  2. What factors effect the rate of reaction at which Alka-Seltzer tablets react with water.

    over the Bunsen Burner and the gauze will be placed on top of the tripod. This set up will be used to heat the tap water. * A 400ml beaker will then be taken and filled with 150ml of tap water.

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