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

'How does the concentration of Sodium thiosulphate solution affect the rate of its reaction with hydrochloric acid?'

Extracts from this document...


'How does the concentration of Sodium thiosulphate solution affect the rate of its reaction with hydrochloric acid?' The aim of my experiment is to investigate how the concentration of Sodium thiosulphate solution affects the rate of its reaction with hydrochloric acid. I am going add water to the sodium thiosulphate solution to weaken the concentration so I can see how it can affect the rate of reaction. I shall add water as that is the only way I can find out how concentration affects the rate of reaction as I cannot increase concentration from 1M upwards as I do not have the resources available to use. Prediction I predict that when I add more water to the sodium thiosulphate solution, the time it takes for the dot on the beaker to disappear will lengthen. I predict this because, for particles to react they must collide with each other. If there is a higher concentration of sodium thiosulphate particles in a given volume there is a higher chance of the particles colliding together succesfully and reacting. This is because they are so close together. If you weaken the solution, (so there is a much lower concentration of sodium thiosulphate particles to react with the hydrochloric acid,) then there is less chance of the particles colliding succesfully and reacting as there are less particles in the given volume, so the reaction time will slowly lengthen as the concentration goes down. ...read more.


Volume of water (cm3) Concentration of Sodium Thiosulphate (mol/dm3) Time taken for dot to disappear (s) Rate of Reaction 1/t ( /s) 10 0 1 5 0.2 8.5 1.5 0.85 7 0.142857142 7 3 0.7 9 0.111111111 5.5 4.5 0.55 10 0.1 4 6 0.4 15 0.066666666 2.5 7.5 0.25 21 0.047619047 1 9 0.1 35 0.028571428 Conclusion I discovered that there was not enough variation in the concentrations. So I decided to change the concentrations I was going to use. I found out that doing seven concentrations was enough as it . I also did not make the tests accurate enough as I do not have a big enough range to draw many conclusions. From these results, they look like they back up my prediction, as the time for the dot to disappear lengthens as the concentration of the Sodium Thiosulphate goes down. I shall now vary the volumes of the water and Sodium Thiosulphate by 5cm3. An example of this would be having 45cm3 of Sodium Thiosulphate and having 5cm3 of water, then 40cm3 of Sodium Thiosulphate and 10cm3 of water. This then would carry on going up or down in either direction as needed, this will give me extra accuracy. Final Experiment Volume of Sodium Thiosulphate Solution (cm3) Volume of Water (cm3) Concentration of Sodium Thiosulphate (mol/dm3) ...read more.


Therefore I think if I repeated this experiment I would repeat the variations at least 4 or 5 times rarther than three times, if I did then my results would be a lot more accurate. Apart from that point I think that I did discover enough information to help me lead to a conclusion. If I would do the experiment again I would use a light sensor to detect whether or not it could see the light through the cloudy reaction. This would mean that the experiment would be more accurate. Also using the same equipment may have a small effect on the results, or cleaning the flasks out after each experiment may help. Another improvement could be to use a water bath to keep the temperature of the reaction the same throughout, as it would not then be affected by the heat from the classroom. I would also do the whole experiment, including the repeats on the same day so no variations can occur because of different days. To obtain more evidence to support my conclusion I would take more of a range of results. I might use more concentrated Sodium Thiosulphate or use less concentrated Sodium Thiosulphate. More evidence would mean that there would be more verification that my prediction was correct, and would solidify the concept of the collision theory. Overall I think I have done an interesting investigation, and have completed it to the extent of my abilities. I have tried to make it a fair test, and back everything up with solid evidence. ...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. Experiment to Investigate the Rate of Reaction between Hydrochloric Acid and Sodium Thiosulphate, with ...

    of hydrochloric acid present a precipitate did not form, as there was no reaction. As a precipitate did not and would not form it means that the time for the reaction would be infinite as it would never happen. In the Results Table 2, which are my second set of

  2. Free essay

    Close Your Eyes

    The conversation we were having went on for about another 10 minutes and Danny was probably wondering where I was. "Ok ok I'm gonna tell him" I eventually said "But, how do I say it?" She sighed. "Now let's think, how could you possibly say it?

  1. An investigation into the effect of Concentration of Sodium Thiosulphate on the rate of ...

    it would decrease the concentration, if it was Sodium thiosulphate, it would increase the concentration). 9. Do the experiment again with different concentrations of sodium thiosulphate. These concentrations are: 1.0M = 25 ml 1.0M Sodium thiosulphate and 25ml 1.0M HCl 0.8M = 20 ml 1.0M Sodium thiosulphate + 5 ml

  2. How does the concentration of sodium thiosulphate solution affect the rate of its reaction ...

    * I will need to use the same cross in each experiment * The size of flask- so that the depth of the liquid is the same. * I will not stir or shake any of the experiment- If I stir or shake any of the experiments I will increase

  1. How does the Temperature affect the Rate of Reaction between Sodium Thiosulphate and Acid?

    The structure of the molecule is being broken down. This allows the molecules to move around faster as they have fewer attractions to other molecules. The other theory is the Collision theory. As just explained when there is an increase in the temperature the molecules gain more energy, thus moving around faster, which in turn leads to the collisions between molecules becoming more frequent.

  2. The reaction between Sodium Thiosulphate and Hydrochloric Acid.

    If it doesn't, then nothing will happen and the particles will bounce off each other. That may seem like a lot to happen for a successful reaction, but at the speeds the particles move about, it takes fractions of a second for them to collide with each other and eventually one sparks off the reaction.

  1. How does the Temperature affect the rate of the reaction between Sodium Thiosulphate and ...

    V2 and T2 are the volume and temperature of the HCL acid, the volume will be 5 ml throughout and the temperature will be room temperature (around 20 degrees Celsius). T3 is the temperature of the sodium thiosulphate and water solution after the HCL has been added and is the

  2. How Does The Concentration Of Sodium Thiosulfate Affect The Rate Of This Reaction?

    I got to know all the apparatus and the method. Word Equation for the reaction: Sodium Thiosulfate + Hydrochloric acid ? Sodium Chloride + Sulphur + sulphur dioxide + water Ionic equation for reaction: 2Na+ + S2O32- + 2H+ + 2Cl- ? 2Na+ + 2Cl- + SO2 (g)

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