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

Investigating the effect of concentration on the rate of reaction between Sodium thiosulphate and hydrochloric acid

Extracts from this document...

Introduction

Investigating the effect of concentration on the rate of reaction between Sodium thiosulphate and hydrochloric acid Plan In this investigation I am going to find out how the concentration of an acid affects the rate of reaction between the two substances Sodium thiosulphate and hydrochloric acid. The rate of reaction is the rate of loss of a reactant or the rate of formation of a product during a chemical reaction. I have chosen to investigate the effect concentration has on a reaction. To do this I will mark a cross below the conical flask the solution is in and time how long it takes to disappear from view. I have decided to keep the concentration of sodium thiosulphate the same (0.2M) and change the concentration of the hydrochloric acid varying between 0.2M and 1M, going up in 0.2's. I will also take 3 results for every different concentration so that I can work out the average and therefore get a more accurate result to plot on my graph. ...read more.

Middle

This increases the probability of reactant particles colliding with each other. This means that the rate of reaction will increase if the concentration of reactants is increased. Apparatus Hydrochloric acid Sodium thiosulphate Water Conical flask Measuring cylinders Pipette Marker pen Paper Safety goggles Stop clock Diagram Method 1) On a piece of paper with a marker pen draw a cross the size of the bottom of a conical flask as shown in diagram. 2) Measure out 50mm3 of sodium thiosulphate in a measuring cylinder and pour into a conical flask. 3) Measure out 2mm3 of hydrochloric acid into a measuring cylinder and then 8mm3 of water into the same one to make it 0.2M of acid. 4) Pour the diluted acid into the conical flask (with the sodium thiosulphate in already) and start timing, stop the stop clock when you cannot see the cross anymore. 5) Record 3 sets of results for each concentration of acid and then repeat these steps with 0.4M, 0.6M, 0.8M and 1M. Record results into a table. Results table Concentration of hydrochloric acid (M) Time taken (s) Average time taken (s) ...read more.

Conclusion

These results support my prediction because I know from scientific knowledge that if the concentration of a solution is increased there are more reactant particles per unit volume which means the probability of reactant particles colliding with each other increases. This proves that the rate of reaction will increase if the concentration of reactants is increased. Evaluation We carried out our experiment exactly the way we planned it and followed our method throughout the experiment. Our results were very accurate because we made sure the variables were kept the same which meant we did not get any anomalous results. This was because we found out the average of 3 results, so even if there were any anomalous ones it would hardly make any difference. My prediction that the time as the concentration of acid increased, the time would decrease was correct but I did not predict that as the concentration was higher the graph would eventually become less steep and gradually fall off towards the end. I could have extended my investigation even further by going past 1M of acid to see if the graph did level off as the concentration became even higher. ...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 chemicl reaction ...

    However, others work in more complex ways. > Surface area When one or more of the reactants is a solid, the more finely powdered the solid, the greater is the rate of reaction. This is because reactions involving solids take place on the surface of the solids.

  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.

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