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

Investigation to find out if changes in concentration of acid Effect the rate of chemical reactions.

Extracts from this document...


Investigation to find out if changes in concentration of acid Effect the rate of chemical reactions. Planning Introduction The rate of a reaction is defined as the speed at which the reaction takes place. Many things can affect the rate of reaction. In this coursework I am investigating what Effect the change in acid concentration will have on the rate of reaction. The reaction between sodium thiosulphate and dilute hydrochloric acid will be used. The concentration of the thiosulphate will be changed; I will do this by adding different amounts of water. The concentration of the acid (hydrochloric) will remain constant. Table of variables Variable Effect Reason Value Temperature A high temperature will speed up the rate of reaction. As the temperature is increased particles move quicker. Increasing the temperature increases the rate of reaction. 10 degrees raise in temperature doubles the rate of reaction. Catalysts Adding a catalyst increases the rate of reaction. It is not used up itself Catalysts speed up reactions by providing an alternative pathway for the reaction. Thus creating more collisions. Speed up the reaction Concentration As the concentration is increased the reaction increases. The greater the concentration the more reactant particles there are in the solution. There will be more collisions and thus the reaction rate is increased. ...read more.


To find the rate of reaction of thiosulphate solution with hydrochloric acid that will vary in concentration. Apparatus: list of the apparatus I will use for the experiment. The apparatus used for the following experiment is shown below: * 150cm� conical flask * 10 cm� conical flask * 50cm� conical flask * 10cm� measuring cylinder * Test-tube * Stop clock * Test tube rack * White tile * Marker pen Chemicals: The chemicals I will use for this experiment. * Sodium thiosulphate * Hydrochloric acid The measuring cylinder is easy to use and it is easy to read from, the marker pen will be used to mark a cross on the white tile. The stop clock is also easy to use and the test tube rack holds the solutions, which is very helpful when carrying out an experiment. Planning Safety Before starting there are a few safety aspects, which we have to be careful of. Firstly, safety glasses should be worn at all times, and secondly, we have to be careful because the acid is highly corrosive to our bodies and should be kept away from skin and from our clothes. Method 1. I put 10cm� of thiosulphate solution into the conical flask. 2. I added 40cm� of water. ...read more.


My prediction was correct as what I predicted happened. Evaluation and Improvements: The main drawback with my experiment was the accuracy. To get the best range of results possible I needed to be as accurate as possible. With my equipment I think that I achieved this, but I could have used more complex measuring devices. I had no anomalies in my results as they all fitted into my pattern on my graph. If I were to do the experiment again I could improve it by using a wider range of concentrations, which would lead to a more accurate line of best fit. I would also have done each reading more than three times and taken a larger average, which would have increased the accuracy. Possible problems with my coursework could have been caused by human error. Firstly, there could have been error in stopping the stopwatch, although this would have been minimal. Also, some of the solution could have escaped If I were to change a variable, I would use the temperature. I think that this would be interesting to see if the rate of reaction was directly proportional. Overall, however, I think that this experiment has been successful because my prediction has been accurate which shows that the results are accurate. I have also made sure that the test was done fairly. ...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. The Iodine Clock Investigation

    Modifications that could be made to increase the accuracy would be to only make up one large batch of solutions, and conduct all of the experiments in one go, taking up no more time than perhaps 48 hours. Secondly, during the preparations of each experiment, the solutions were measured out

  2. An investigation into the effect of concentration on the rate of reaction. The disappearing ...

    * Keep bags and stools under the bench to allow a better and safer working environment. * Stand at all times when conducting the experiment to reduce the risk of tripping and spilling chemicals. * Take care when using the chemicals and equipment during the experiment - especially the hydrochloric acid as it can irritate the skin upon contact.

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

    The highest temperature will be 60.0 oC because as observed in the background research, any temperature above this would lead to the acid evaporating. Each temperature should be repeated twice in order to rule out any anomalous results. This will then improve the reliability of the experiment.

  2. Find out how the rate of hydrolysis of an organic halogen compound depends on ...

    It is given by the shaded area underneath the curve. Only those collisions with energies in the shaded area can lead to a reaction. (The shape of the energy distribution curve for collisions is the same as for individual molecules.)

  1. An Investigation into the effect of Acid Concentration on the Rate of Reaction

    Another interesting observation was the decrease in effervescence as the acid concentration lessened- showing yet again a decrease in the rate of reaction. Strategy The strategy I will use to determine the rate of chemical reaction will be to measure how fast the gas will be produced;.

  2. Investigate and conclude what factors affect the rate of a chemical reaction, and specifically ...

    When the reactant is crushed into many smaller pieces (right) however, the surface area is greatly increased. Thus, resulting in more particles being able to collide and therefore a much higher collision frequency.

  1. What is the effect of concentration on the rate of a chemical reaction?

    This would mean more particles moving around in the same space and that means more chances of a collision, in which two particles will join and form a new substance. In figure one the opposite of figure two will happen.

  2. What factors effect the rate of a chemical reaction?

    Conversely, reducing the temperature will decrease the amount of energy, slow down movement and decrease the number of collisions. All reactions need energy to start them off. The activation energy is the minimum energy needed to break enough bonds to start a reaction.

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