• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11
  12. 12
    12
  13. 13
    13
  14. 14
    14

Rates of Reaction

Extracts from this document...

Introduction

Rates of Reaction AIM In all chemical reactions products are formed and reactants are used up. The following are factors, which affect the rate of reaction: * Surface area of solid reactants. * Changes in concentration of solution in which reactant is placed. * Changes in Pressure (if reactant is gas). * Changes in Temperature. * Catalysts. I will be investigating the affect concentration has on the rate of reaction between Magnesium and Hydrochloric Acid. The reactants in this investigation are the magnesium ribbon and the hydrochloric acid. The products are Magnesium Chloride and Hydrogen (gas). The following equation demonstrates this: Mg(S) + 2HCl(AQ) MgCl2(AQ) + H2(G) Magnesium + Hydrochloric Acid Magnesium Chloride + Hydrogen I must remember that most of the factors listed above will in some way affect the rate of reaction i.e. the Surface area of the Magnesium ribbon, the temperature of the Hydrochloric Acid. PREDICTION From previous experiments I have discovered that the rate of reaction is directly proportional to the concentration. When Dilute Hydrochloric acid and sodium thiosulphate react, the higher the concentration the faster they react. I also noticed that as the concentration doubled the rate also doubled. I predict that as the concentration of Hydrochloric acid doubles the rate of reaction will also double. SCIENTIFIC KNOWLEDGE For all Chemical reactions there is a rearrangement of atoms. We can see this by looking at a simpler chemical reaction like the production of Water (H2O). + Hydrogen Oxygen Water Molecules molecule Molecule In order to form Water the Hydrogen and oxygen molecules must collide! Particles in liquids are in constant motion (Kinetic theory). Kinetic theory derived from the concept of Brownian motion discovered by a botanist called Robert Brown in 1827. He discovered that tiny molecules in a liquid or a gas would make suspended particles move when they collided. From this we can make judgements. In order for the larger particles to move the molecules in the liquid must have been moving at a relatively fast speed. ...read more.

Middle

As soon as the lid is on start the timer. * Make sure exactly 25cm� of H2 has been collected and then stop the timer. * *To find the average, we will calculate the sum of the 3 times for each concentration, we will then divide this sum by 3. This is done so the results will be more reliable. * I will record time in seconds and to one decimal space, for accuracy. * I will repeat any results, which seem anomalous. SAFETY PRECAUTIONS I must give a lot of consideration to the safety aspects of this investigation for the sake of fellow students and myself: * As I will be handling HCl, which is an irritant, I must have eye protection and when handling the more concentrated solutions should have some kind of skin protection. I must generally be careful when handling the acid. * As I will be using a lot of glass apparatus which is sharp when broken I must be aware of this during the experiment and when putting all the apparatus back. * I must take care when it comes to the disposal of chemicals. RESULTS The following table contains the time taken to collect 25cm� for all three experiments and the average time for each concentration has been calculated. Concentration of HCL (M) Experiment 1 (Seconds) Experiment 2 (Seconds) Experiment 3 (Seconds) Average Time (seconds) 2 4.4 5.3 5.1 4.9 1.8 5.9 6.2 7.1 6.4 1.6 7.8 8.1 8.3 8.0 1.4 10.5 11.2 11.1 10.9 1.2 15 14.7 14.8 14.8 1 23.5 23.5 22 23 0.8 40.6 78.6 38.9 52.7 0.6 63.2 367 243 224.4 After observing the results I gained from the experiment, I can see some results, which seem anomalous, they will affect the shape of the curve and thus I will not be able to make accurate observations. The figures in the table above, which have been highlighted red are the ones which I don't think are correct. ...read more.

Conclusion

* The reaction between Magnesium and HCl is an exothermic reaction. Heat is spread to the surroundings. Thus, raising the temperature of the solution, this adds to the rate of reaction. The following are improvements I would make for any further investigation: * Use Magnesium filings, as the impact of H2 molecules on the surface would not be as much as Magnesium ribbon. * Take a lot more care when measuring all solutions. * Making sure the containers are always dry on the inside. * When measuring out concentrations I should double check whether the right amounts of HCL and water have been added together. * I could use a gas syringe to collect the gas this would be more reliable than the displacement of water and their would be less faults in the timing of when 25cm� of H2 is collected. * I could use computers to construct graphs, which would give me more accurate best-fit lines, which I could read of. To improve my investigation I can take other factors into account and observe how they would affect the rate of reaction, the following factors are worth considering: * Surface area - If I were to carry out such experiment I would predict that as the surface area of the Magnesium increased, there would be a higher rate of 'successful' collisions, which would increase the rate of reaction. * Temperature - I would predict that as the temperature increased the rate of reaction would increase. The higher temperature provides the particles with higher energy levels so more particles posses' energy greater than the Activation Energy (Ea) so collide 'successfully'. * Use of a catalyst- a catalyst can alter the rate of reaction be reducing or increasing the Activation Energy (Ea) for a particular reaction. If a Catalyst, which reduces the Activation Energy (Ea) for particles in the reaction between Magnesium and Hydrochloric Acid. This would result in a higher proportion of 'successful' collisions. Thus increasing the rate of reaction. Maryam Shah 17637/8503 ...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

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. Rates of reaction between Magnesium and HCl.

    Average rate of reaction (cm�/second) 1.0 0.25 0.9 0.21 0.8 0.15 0.7 0.12 0.6 0.09 0.5 0.06 0.4 0.05 0.3 0.03 0.2 0.02 0.1 0.01 From the graph above it is clear that as the concentration of the hydrochloric acid increases, so does the average rate of reaction.

  2. Investigating the Rate of Reaction Between Hydrochloric Acid (Hcl) and Magnesium (Mg).

    When the experiment was started the bung had to be taken off to put in a piece of magnesium. The bung had to then be placed back on very fast, as to let no gas escape. However, gas particles move faster than the human hand, and may have escaped before the bung was placed back on.

  1. Determine the rate equation for the reaction of hydrochloric acid with magnesium metal, and ...

    bubbles of a colourless, odourless gas were being produced on the magnesium grains. The boiling tube warmed up during the experiment indicating that the reaction was exothermic. Results The results are tabulated below. Time /s H2(g) produced /cm3 Test 1 H2(g)

  2. Rates of reactions between HCL and magnesium ribbon.

    is not very pure or it may be too hot or too cold, or I could use distilled water. Tap water may have some things in it that may affect the results. The temperature also could affect the experiment because if heat is applied then the particles would move around more and affect the.

  1. Rates of Reaction experiments

    Errors There is one suspected anomalous readings in my results from this investigation taken in the first set, for the temperature of 30�C (see Table 1) The anomalous readings from the first set give slower reaction rates for increased temperature which is not a trend shown by any other results in Table 1.

  2. The aim of this investigation is to find out the effect of concentration of ...

    concentration~1/time,such as 1)When the reaction takes place bubbles of H2 are given off ,which might stay around the magnesium which therefore reduces the surface area of the magnesium and so the acid cannot react properly so this effects the results.

  1. Find out how different concentrations of HCl affect the rate of the reaction with ...

    A strong acid is one in which all the hydrogen ions are completely dissociated and a weak acid is one in which the hydrogen ions are not completely dissociated or they are partly dissociated. HCl is a strong acid and CH3COOH is a weak acid. HCl(g) + H2O ----------> Cl�(aq)

  2. Investigating making Epsom salts by varying the rates of reaction.

    Prediction: What I predict is that the more concentrated the solution is the more reaction would take place which would mean that more hydrogen would be produced and as the concentration levels decrease the reactions would become weaker and less hydrogen would be produced.

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