• 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
6. 6
6
7. 7
7

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

Extracts from this document...

Introduction

'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.

Middle

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.

Conclusion

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

# Related GCSE Patterns of Behaviour essays

1. ## Experiment to Investigate the Rate of Reaction between Hydrochloric Acid and Sodium Thiosulphate, with ...

Also at 0.06 Mol.dm-� for Graph 1 it takes 68.00 seconds but for Graph 2 it is 88.00 seconds. Again this shows that the first set of results had the fastest reactions as they took a shorter time to occur.

2. ## How does temperature affect the rate of reaction between Hydrochloric acid and sodium thiosulphate ...

this was very difficult to keep constant so therefore the starting temperature may not be completely reliable. The temperature was at some points slightly too high then too cold by a few degrees and so the time taken for the reaction to complete may have a measure of inaccuracy.

1. ## The reaction between Sodium Thiosulphate and Hydrochloric Acid.

This ties in with the scientific explanation that I described in my experiment plan. Because the concentration is greater, it means that there are more particles and so the chances of collision are increased. If there is a greater chance of a collision then there is also a greater chance

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

I must also use the same volume of Hydrochloric acid as Sodium thiosulphate (25 ml). In the experiment, I must also control the use of temperature, surface area (in experiment pressure), and the use of catalysts. I will control this by only varying the concentration of one reactant (sodium thiosulphate)

1. ## An investigation into the effect of changing the concentration of the sodium thiosulphate solution ...

I will not have to keep this constant, as I am not using a catalyst in my experiment. * Trial Experiments I performed five trial experiments. I did this to find good concentrations and volumes for my final experiment. I did the experiments with the highest concentration and the lowest

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. ## An investigation into the effect of concentration on the rate of chemicl reaction ...

thiosulphate solution in the experiment and also to find out what concentration of Hydrochloric acid should I use for my investigation. The result shows that 0.1 M and 0.2 M concentration of Hydrochloric acid with 0.3 M of sodium thiosulphate, there were no reaction as this take too long for cross to disappear.

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

+ S + H2O (l) Balanced Symbol Equation for the reaction: Products Reactants Na2S203 (aq) + 2HCl (aq) ? 2NaCl (aq) + S (s) +SO2 (g) +H20 (l) I only did the experiment one, not three times so I did not get an average time for each concentration.

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