These are my preliminary results I based my prediction on these.
This informed my plan because it gave me a slight idea of what the results might look like and I know how to carry out the experiment.
I would know if the experiment were taking too long by judging the preliminary results.
I done the preliminary to see how I could do it better the next time I done the experiment
Sodium thiosulphate + Hydrochloric acid → Sulphur Dioxide + Sodium Chloride + Water
Factors which affect the rate of reaction
Catalysts
Temperature
Concentration All affect the rate of reaction
Surface area
When you increase the temperature the atoms move around a lot more and a lot faster and so they will collide quicker and more frequent. If the atoms move more they will also collide more therefore making the reaction quicker.
Apparatus
6 Conical flasks
6 Measuring cylinders
Stopwatch
Hydrochloric acid 120cm3
Sodium Thiosulphate
Cardboard Cross
Bunsen Burner
Ice
Thermometer
Tripod
Tongs
Splint
Wire Gauze
Match
Method
We either heat or cool the Sodium Thiosulphate to the desired temperature and we put the conical flask on the ‘X’. We then add the acid and time how long it takes for the ‘X’ to disappear. We will not contaminate the two liquids, to prevent this we will use separate equipment for the Thiosulphate and the acid. To make it a fair test we will use equal amounts of thiosulphate and acid measured carefully in a measuring cylinder.
I will be doing the experiment at a range of 5oC, 15oC, 25oC, 35oC, 45oC, and 55oC. This way it makes it more accurate when it comes to drawing graphs. I will repeat the experiment three times.
Conclusion
My results show that as the temperature increases the rate of reaction increases.
I know this because I have done it in my preliminary experiment.
I have done a range of 5 to 55 degrees Celsius.
As I heat the experiment the atoms move around more and there will be more collisions the amount of energy they have when they collide is called the activation energy.
My results back up my prediction, which stated ‘I predict as you raise the temperature the rate of reaction will increase’. My results prove this.
Evaluation
My measurements were very accurate because I measured it myself.
If I had used a burette my measurements would have been more accurate.
There were no abnormal results in my experiment I know this because on the graph the results form a smooth curve, I believe that my results are accurate because I repeated the experiment three times.
To get other results I wound use concentration and temperature.
I would use different concentrations like ¾ acid and ¼ thiosulphate.
I would also use a more accurate range of temperature like 5oC to 55oC but I will go up in five degrees at a time instead of ten degrees at a time. I could get the temperatures more accurate I could use an electric heater or a water bath. I would use these because it would stay at the temperature. I would also heat both liquids to make it more accurate and fair experiment.
By Kyle Clark