• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5

# Investigate the principal factors that affect the rate of reaction between Sodium Thiosulphate and hydrochloric acid.

Extracts from this document...

Introduction

Rates Of Reaction Coursework Aim: To investigate the principal factors that affect the rate of reaction between Sodium Thiosulphate and hydrochloric acid. Theory: The reaction between sodium thiosulphate solution and dilute hydrochloric acid: HCl+sodium thiosulphatesodium chloride+sulphur dioxide+sulphur+water. HCl(aq) + Na2S2O3(aq) NaCl(aq) + SO2(g) + S(s) + H2O(l) The sulphur formed in this reaction makes the colourless solution go cloudy. The reaction is usually carried out in a flask placed on a piece of white paper which has a black cross on it. At the beginning of the reaction, the cross can be seen easily. As the flask becomes more and more cloudy, the cross gets harder to see. Factors which affect the rate of reaction: * Increasing the temperature of a reaction increases the rate of a reaction. At the higher temperatures reactant particles move faster and collide more often and more violently. For every 10?c rise in temperature, the rate of reaction doubles. * Increasing the concentration of reactants increases the rate of a reaction. This is because there are more particles in the same volume so more collisions are possible every second. ...read more.

Middle

Although my results did not completely satisfy this statement, there is some evidence to prove it. At high temperatures, the rate of reaction is very rapid; therefore the time for the reaction to take place is quite small. If you lowered the temperature by 10?c you would expect the time for the reaction to double (20 secs for 50?c, 40 secs for 40?c). My results were very similar to these model results but not always exact. The theory that the rate of reaction doubles for every 10?c rise in temperature always gives a curved graph, it will never be a straight line. My graphs for temperature versus time show this very well. My other prediction was that increasing the concentration of the reactants would increase the rate of reaction. My results agree with this prediction. Concentrated sodium thiosulphate reacted a lot faster than dilute sodium thiosulphate. The results go down fairly steadily on the graph but the 25cm? result could be an anomalous result. This result could be correct. The line of best fit is wrong as it says that the solution will go cloudy in 209 seconds when there is no sodium thiosulphate present. ...read more.

Conclusion

This caused a drop in temperature when the sodium thiosulphate and acid were mixed. This is not important as it is a systematic error (it happened every time and made the temperature drop by the same amount). This could explain the reason why the rate of reaction did not always double for every 10?c rise in temperature. The beakers used were washed before each experiment. There was no chance of contamination from other chemicals as they were all washed with sodium thiosulphate before hand. Future Investigations/Improvements: If I could do the experiment again, I would make a few changes. These changes would give more accurate and also a wider range of results. I would use a magnetic stirrer as opposed to hand if possible. The magnetic stirrer can be set to a certain speed and remains at that speed for the whole experiment. I would use light sensors to decide exactly when the reaction had reached the completion point, as they are far more accurate than the eye. I would repeat each experiment at least 3 times to ensure that the results are accurate. I would heat the acid as well as the sodium thiosulphate when investigating temperature. This would mean that the acid wouldn't cool down or heat up the solution. ...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

# Related GCSE Patterns of Behaviour essays

1. ## The aim of this coursework is to investigate the rate of reaction between sodium ...

In this experiment, we decided to investigate the effect of concentration on a reaction between sodium thiosulphate and hydrochloric acid. When we talk about the concentration of a solution, we generally look at the amount of a specific substance in that solution.

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

This is because it has the least percentage error. When we come to do the actual experiment that will be the concentration that will be used and then the only variable changed will be the temperature whereas in the trial experiment the variable changed was the concentration. THE ACTUAL EXPERIMENT Apparatus: * Bunsen Burner - To heat up the

1. ## To investigate the effect of varying the masses of white sugar and yeast and ...

The findings described in Pyler relative to the gassing power of yeast action on carbohydrates are interesting and of value to the baker. For example, if 100 lb of flour will yield approximately 180 lb of dough, the degree of expansion in the dough during fermentation and proofing can be sustained by about 3.5% of fermentable carbohydrates, based on flour.

2. ## Investigating the factors influencing the rate of reaction between Sodium Thiosulphate and Dilute Hydrochloric ...

This means that when the solution becomes opaque, the assumption I can make is that the reaction is complete; therefore, I will stop the stop clock. As the Sodium Thiosulphate solution is diluted, the precipitate took longer to form. Both the Sodium Thiosulphate and hydrochloric acid are soluble in water, so either of the solutions can be altered.

1. ## HCL and sodium thiosulphate - investigate which factors affect the rate of reaction.

Enzymes are naturally occurring catalysts responsible for many essential biochemical reactions. Caseous and liquid catalysts are commonly dispersed in other substances known as catalyst support. A catalytic action is a chemical reaction between the catalyst and a reactant, forming chemical intermediates that are able to react more freely with each other or with another reactant.

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

If more reactions are taking place in a shorter space of time as the temperature increases then more sulphur will be produced per second as you raise the Temperature. This means that the more you raise the temperature the quicker the amount of sulphur required for the person judging the experiment to be unable to see the cross.

1. ## I aim to investigate the affect of temperature on the rate of reaction between ...

In this experiment we are only interested in temperature. Where temperature is not high enough to provide energy for the particles to move at a high enough speed, the particles will just not react. Basically, not as many particles will be able to react together in a certain amount of time.

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

All acids contain hydrogen ions (H+): this makes them acids. The more hydrogen ions an acid contains, the more acidic it is. Definition of an acid: a substance that produces that produces H+ ions when dissolved in water. Strong acids produce a lot of H+ ions.

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