• 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

Investigation into the effects of concentration of reactants on the rate of reaction.

Extracts from this document...


Investigation into the effects of concentration of reactants on the rate of reaction. Introduction My knowledge about the reaction between "thio" and dilute hydrochloric acid is that sodium thiosulphate reacts with the hydrochloric acid to form sodium chloride (aq) + water (l) + sulphur dioxide (g) + sulphur(s) one of the interesting things about this reaction is that it products are all the different possible states aqua's, liquid, gas and solid. The symbol equation for the reaction is Na2 S2 03 + 2HCl = 2NaCl + H20 + So2 + S. What actually occurs when dilute hydrochloric acid is added to "thio" is that the solution gradually turns cloudy as a pale yellow precipitate forms, the pale yellow cloudiness is sulphur, which is not soluble in water. This knowledge I have acquired when doing an experiment into the effects of heat on the rate of reaction between "thio" and dilute hydrochloric acid. Trial run The results from my trial run are as follows: - 25ml of thio, 5 ml of acid 5ml of thio, 20ml of water, 5ml of acid Time: 38 seconds 5 minutes 7 seconds 5 minutes 2 seconds The things that I am going to change about the method are: - I am going to use burettes instead of measuring cylinders for measuring the water and the thio because burettes are accurate to +/- 0.2% whereas measuring cylinders are only accurate to +/- 2%, burettes are 10x as accurate. ...read more.


Conclusion The graphs in my prediction are very similar to the ones that I plotted after obtaining my results; the one showing rate against concentration of reactants shows direct proportion (graph 2) and in the one showing time against concentration of reactants shows inverse proportion (graph 1). As I stated in my prediction as the concentration doubles so roughly does the rate, this shown by the rate for 8g/l (0.43) and 16g/l (0.97). It is also vindicated in the rate for 16g/l (0.97) and 32g/l (1.88). This agrees with my prediction because as stated there if you double the concentration of thio you double the number of particles which doubles the number of particle collisions and gives double the number of successful collisions which leads to the same amount of sulphur being produced in half the time therefore doubling the rate. My results point to a firm conclusion because the repeats have good agreement, they are close to the line of best fit on the graph and my conclusion is in line with my prediction. I did however have one or two anomalous results but I left them out of my averaging so they don't affect my overall results. Evaluation The points on my graph are quite close to the line of best fit a few are a short distance from it but this can be accounted for I believe by the temperature fluctuation in the classroom at the time of the experiments. ...read more.


Paper with cross- helps measure how long reaction takes. Step by step plan 1.Collect apparatus 2.Measure out acid and dilute with water if necessary (using burettes) into 50ml conical flask. 3.Place thermometer into acid. 4.Measure out 25ml thio using burettes. 5.Take temperature of acid when it is steady and then record it. 6.Place conical flask on paper with cross. 7.Add thio to acid solution and start stopwatch simultaneously. 8.Stop the stopwatch when cross disappears and record the time. Repeat experiment at least twice for each concentration. Safety For safety we will: - Cover eyes with safety goggles. Wash up all spillages of acid or thio solution immediately. Rinse away solution immediately after reaction to minimise problems with sulphur dioxide causing asthma attacks. Prediction I predict the trend in my results will be as follows: - Graph 1 Graph 2 In graph 1 I am showing an inverse relationship because as the concentration increases the time decreases. In graph 2 I am showing direct proportion because as the concentration doubles so does the rate of the reaction this is proved by the straight line. The reasoning behind this prediction is that: - Double the concentration of acid- double the number of particles- double the number of particle collisions- double the number of successful collisions- same amount of sulphur produced in half the time. ?? ?? ?? ?? Huckleberry Briscoe 10CD Chemistry Mr. Ness ...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 Aqueous Chemistry 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 Aqueous Chemistry essays

  1. My Aim is to see how concentration of acid will affect the time it ...

    From this I can conclude that my results show that the rate of reaction increases with the increase in concentration. This idea supports my prediction because this is what I said as a general rule. However it only partially supports my idea that double the concentration, double the speed which

  2. Investigating the effects of changing the concentration of different solutions on the refractive index ...

    ( corresponding angle & alternate angle) (provided that the ray from O to P is near the normal ==> i and r are small angles ==> PO = OS & PO' = O'S) r P S r i O' i O Diagram 6 Diary Day 1 I was reading some typical examples of A Level experiments from several text books.

  1. Rates of Reaction

    is a much smaller collision frequency this means that there is less chance of an acid particle colliding with the calcium carbonate molecule due to the concentration. B) In flask B the acid is much more concentrated (simply meaning that there are much more acid particles contained in it).

  2. What effects the rate of a reaction

    We can see how magnesium was affected by taking the different time lengths it took the magnesium to disappear in the different concentrations of solution. I can then compare the percentage increase or decrease in time. Aim: To find out how the concentration of a solution affects the rate of a reaction.

  1. Rate of Reaction

    In a solid though the bigger the surface area the faster the rate of reaction. This is because when the surface area is larger there are more surfaces for the particles to react with. Breaking it up into smaller pieces increases the surface area of a solid.

  2. Investigating the Effects of Increasing Copper Sulphate Solution Concentrations on the Germination of Cress ...

    p Values 0.10 0.05 0.01 0.001 14 1.76 2.15 2.98 4.14 This shows that the p<0.001. This means that the results are very highly significant and that I can reject my null hypothesis and be almost certain that the mean number of seeds germinated in concentrations 60mg/l and 0.06mg/l are significantly different.

  1. Investigating On How Concentration Effects The Rate of Reaction

    When we started our 1st trial run we obtained all the equipment we needed and we laid everything out so here was space and nothing was crowded because this is a safety hazard we then put our goggles on and we began the 1st trial run.

  2. &amp;quot;What Affects How Quickly Sodium Thiosulphate (thio) Goes Cloudy?&amp;quot;

    resulting in fewer collisions as the atoms would have more space to move around in and they would not collide as often. Prediction For this experiment, I predict that the higher the concentration of sodium Thiosulphate, the faster the rate of reaction will be, this is because, there would be

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