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

Rates of Reaction Course Work.

Extracts from this document...

Introduction

Chemestry Rates of Reaction Course Work Introduction/Aim: This coursework is about the investigation of the effect of concentration on the rate of reaction between Sodium Thiosulphate (Na2S2O3) and Hydrochloric acid (HCL) by simply changing the concentration of Sodium Thiosulphate. I made a set of results which were obtained by using the method of 'precipitation'. This is when the product of the reaction is a precipitate, which clouds the solution. One observes a marker through the solution and measures how long it takes for it to disappear. Plan: In order to make it a fair test the volume of hydrochloric acid had to be kept constant each time (5cm�). What had to be changed was a) the amount of Sodium Thisulphate and b) the amount of water. We decided our total volume to be 55 cm�, 5 cm� of that hydrochloric acid, so the rest consisted of Sodium Thisulphate and Water. To obtain our resultes we used the following "Method": Step 1: After setting up everything we first used a measuring cylinder to measure the amounts of Sodium Thiosulphate, Water and Hydrochlorid acid needed. We put the added amount of water and thiosulpahte (which has to be 50 cm�) into a connical flask which will be placed on a paper marked with a cross ("X"). After that we take the measuring cylinder with the 5 cm� of HCl and pored it into the conical flask. Step 2: The stopwatch was started as soon as the first drop of HCl got in. ...read more.

Middle

Volume of H2O (cm3) Volume of HCl (cm3) Total Volume (cm3) Time (s) 10 40 5 55 26.00 15 35 5 55 23.53 20 30 5 55 12.80 25 25 5 55 10.16 30 20 5 55 10.09 35 15 5 55 7.26 40 10 5 55 6.69 45 5 5 55 5.94 50 0 5 55 5.66 The set of results you can see above were taken during all of the experiments. All of the experiments were repeated 2 times in order to receive correct and accurate results. The next step would be to do some calculations with these results. * During all of the experiments it was made sure that the volume of the total solution was always 55 cm� * In all of the experiments the volume of the hydrochloric acid was always 5 cm� These are the calculations i added to my table of results: Concentration = original concentration x volume of Na2S2O3 /total volume of diluted Na2S2O3 i.e., For 30 cm3 of Na2S2O3 used = 1 x (30/50) = 0.6 M Rate = Mass of solid sulphur formed/time taken = 1/time i.e., for 30 cm3 of Na2S2O3 used = 1/time = 1/10.09 = 0.99 Table of results, including the results of all of the calculations: Volume of Na2S2O3 (cm3) Volume of H2O (cm3) Volume of HCl (cm3) Total Volume (cm3) Concentration of Na2S2O3 (M) Time (s) Rate of reaction 10 40 5 55 20.00% 25.24 0.04 15 35 5 55 30.00% 17.56 0.056 20 30 5 55 40.00% 13.69 0.07 25 25 ...read more.

Conclusion

I didn`t have any anomilus results which proves that the message i have used worked in a sence of successfullness and rilableness. Altough the resulats are ok I still have to say that the procedure could have been more accurate. Especially when you take a look at the measuring devices and the method you`ll realise that they could have been more presice in order to obtain better results. It�s also not very easy to decide when exactly to stop the watch, as it is never really clear when the moment was, when the black cross-disappeared behind the cloudy solution. If i had the chance to do this experiment again i would change, include or put more attiontion on the following points: 1. Try to use better, more accurate equipment that includes: - Glass pipettes instead of plasic ones which were used to measure out the liquit. - A different device to determine when the solution has reached a certain level of cloudiness. I am sure that there are specific devices, which do exactly that. - A little apparatus, which pours the substances into the conical flask, and in the same time start the stopwatch. - More accurate measuring cylinders one can make sure that the volumes of the substance are accurate. 2. I would try and use different chemicals in order to see if it effects the rate of reaction. 3. I would do exactly the same experiments but change the amount of solution taken from each substance. 4. I would repeat the experiment one more time so that i have alltogehter 3 sets which will lead to more accurate results and averages. ...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. Investigating Rates of Reactions

    Run 1 (cm�) Run 2 (cm�) Run 3 (cm�) Average volume of gas produced (cm�) 50cm� HCl 0 0 0 0 0 50cm� Water 5 5 4 5 4.5 10 10 9 9 9 Initial temp: 18�C 15 16 14 13 13.5 Final temp: 19�C 20 21 18 18 18 25 24 22

  2. Free essay

    Close Your Eyes

    to find this place and now I'm here you tell me there's no song? Well thanks a lot Danny, waste of my time." Ok so maybe I exaggerated a bit but it was fun to see his reaction. He was staring at me in disbelief and then suddenly started apologizing

  1. Science Course Work

    As the amount of hydrochloric acid particles increase so does the chance that they will hit the Sodium thiosulphate particles because there are now twice as many hydrochloric acid particles at 1.0 molar then when the concentration of hydrochloric acid was 0.5 molar.

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

    I will then wash the flask out and make sure the stop clock has been reset and repeat this experiment again and record the time of reaction again so that I can work out an average time for this test.

  1. Investigation exploring rates of reaction, using the reaction between sodium thiosulphate and hydrochloric acid ...

    by evaporating off most of the water in them. Task: To find out what factors affect the rate of reaction between sodium thiosulphate and hydrochloric acid. Variables Temperature of environment Concentration of hydrochloric acid Concentration of 'hypo' (sodium thiosulphate) Volumes of reactants When hydrochloric acid is added to a solution

  2. Safety To investigate the effect of concentration on the rate of reaction between sodium ...

    * The piece of paper with the cross on it, to ensure that accurate readings can be taken. * The same person will be taking the readings to make the results accurate. In the reaction between Sodium Thiosulphate and dilute Hydrochloric Acid, HCl + Sodium Thiosulphate Sodium Chloride + Sulphur Dioxide + Sulphur + Water HCl(aq)

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