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

An experiment to investigate the effect of changing the concentration of hydrochloric acid on the rate of reaction with sodium thiosulpahte.

Extracts from this document...

Introduction

An experiment to investigate the effect of changing the concentration of hydrochloric acid on the rate of reaction with sodium thiosulpahte. Aim I am trying to find out how the concentration of hydrochloric acid affects the reaction time with sodium thiosulpahte. If a clear solution of sodium thiosulphate is mixed with hydrochloric acid then a reaction will occur where a creamy-yellow precipitate of sulphur is produced. Reactants Products The sulphur takes a while to form and starts to turn the water cloudy after a short time. You cannot tell when the reaction has stopped so a cross drawn on a piece of paper in pencil can be sued to do this experiment. The liquid is placed on top of the cross in a beaker and it is timed how long it takes for the cross to disappear when viewed through the liquid. This experiment can be used to investigate the effects of concentration and temperature on rate of reaction. This is the experiment I am going to do because I am trying to see how the concentration of acid affects the rate of reaction. ...read more.

Middle

* Draw a cross on a piece of paper and place the conical flask on it. * Measure out 10ml of acid and add it to the conical flask and start timing. * Look into the top of the conical flask and when the cross can no longer be seen stop the stop watch. * Do the experiment again but measure out 8ml of hydrochloric acid. Then add 2ml of distilled water. The ratio for each experiment will therefore be 10:0, 8:2, 6:4, 4:6 and of acid to water Conclusion I conclude that whilst carrying out this investigation I found out that the more acid was in the solution the cross on the paper disappeared quicker. This shows that the more concentrated the acid is then the quicker the reaction time. My research about the collision theory was correct and the more concentrated the solution is then the number of collisions will be increased. If the numbers of collisions are increased then the reaction time will also be increased. My prediction 'that the less concentrated the acid is then the longer it will take for the sodium thiosulphate to react with ...read more.

Conclusion

These results aren't adequate for a firm conclusion as it has a few anomalous results and on the average times they don't have a large enough gap between them e.g. 34 and 36. The experiment should be carried out more times for a more accurate result. The procedure used was suitable but produced quite unreliable results as the cross on the paper may have not fully disappeared when the other person was told to stop the timer as this is what we did. If the person looking at the cross and observing when it disappeared changed then the person's opinion on when it has disappeared may make it an inaccurate test so it would have to be kept the same person all the time. If I did the experiment again I would probably take more time measuring out the solutions and it would probably be a better idea for the person observing to see when the cross can no longer be seen to have the stop watch so they can stop it at the exact time they can no longer see it. It could also be improved if the experiment was carried out more times as a better average could be produced. This would make the results more accuarate. ...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. An investigation into the effect of concentration on the rate of reaction. The disappearing ...

    Also, on my graph there is a positive correlation, with the concentration and the rate of reaction being inversely proportional, this is something I expand on in my prediction and predict to happen in my real test. I have also found that my method of experimentation of repeating each test

  2. Experiment to investigate how changing the concentration of hydrochloric acid affects the rate of ...

    Observation of reaction What happens to the chalk? What is the rate of reaction between chalk and hydrochloric acid? Chalk Exothermic A lot bubbles come out It dissolves 4 If the chalk dissolves then it is not re-usable after the reaction.

  1. Find out how the concentration of the reactants affects the rate of reaction between ...

    Controlling the Variables I will use two separate measuring cylinders for the chemicals (sodium thiosulphate and hydrochloric acid) so that the chemicals are not mixed when they are being measured and begin to react I will use two separate small beakers for each of the chemicals (sodium thiosulphate and hydrochloric acid)

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

    yellow in light, and there was little or no change in the colour of silver iodide under light. The rate of the reaction is calculated via the following: For each haloalkane, rate = amount of AgNO3 needed to obscure the cross reaction time for precipitate to form The amount of

  1. Investigating the effect of changing temperature on the rate of reaction between Sodium Thiosulphate ...

    I added these two together in the beaker. The appropriate temperature was checked using the thermometer. It was at this point where I carried out the various temperatures. At the appropriate temperature, 5cm? of hydrochloric acid was measured using the measuring cylinders and then added to the flask containing the sodium thiosulphate.

  2. An Experiment to Investigate the Effect of Changing the Concentration of Hydrochloric Acid on ...

    Independent Variable The independent variable is the concentration of hydrochloric acid. I will vary this concentration by diluting a 1 molar solution of Hydrochloric acid with increments of 5cm� of distilled water for each experiment. I expect to see a trend of change in the reaction time as the concentration of hydrochloric acid is changed.

  1. To investigate the effect of changing the concentration on the rate of reaction between ...

    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. In a cold reaction mixture particles If we heat the reaction mixture are moving quite slowly the particles the particles will move quickly

  2. To investigate by the use of an experiment to measure the effect of changing ...

    Therefore the margin for error in this is quite high, and thus would give me inaccurate results. Hence another method will clearly have to be devised in order to investigate on the rate of reaction, in a more accurate way!

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