I am going to draw a graph analyse by results properly. I am, however due to my line of enquiry, going to change the temperature of the solution. Furthermore I will be careful not to spill anything and will take extra care when doing the experiment.
I will keep everything constant apart from the variable I am changing-temperature. Next I will place the conical flask on top of the cross, pour 5cm3 of hydrochloric into the hot sodium thiosulphate solution and time how long it takes for the cross to disappear.
As the temperature increases, the time taken for the sodium thiosulphate solution to become cloudy decreases. Results Below is a table showing my results from the main investigation I can see from observing the table that the first part of my prediction was correct.
I could also change the initial volume of either the hydrochloric acid or sodium thiosulphate solution and see if I get a similar pattern of results. I will also try to make my timing and the heating of the sodium thiosulphate solution as accurate as possible.
This is because as the temperature increases, the reactant particles move more quickly. Therefore, I will make sure that I only change the temperature of the reaction mixture and keep the volume and concentration of the sodium thiosulphate, the volume and concentration of hydrochloric acid and the pressure of all the mixtures the same.
Safety I will make sure I handle the sodium thiosulphate solution and hydrochloric acid with care.
This means more of the particles collide and more of the collisions result in a reaction, so the rate of reaction increases. On each experiment I will take three readings and work out an average from the data I have obtained.
To further investigate the decomposition of sodium thiosulphate I could change the concentration of hydrochloric acid and sodium thiosulphate or use a catalyst in the reaction. It also has a line of best fit to show the consistency and accuracy of the results. I will also be careful when heating up the solutions and will at all times wear safety goggles and also remain standing throughout the experiment.
Evaluation All of my results were accurate and fitted the pattern of results. The range of my results were also suitable to make good observations and conclusions By comparing the repeated times on each of the experiments I can see that they were similar and each one was within two seconds of each repeat.
From this evidence I believe my results were very reliable. The independent variables will be the initial volume and concentration of sodium thiosulphate, and the initial volume and concentration of hydrochloric acid. This might have occurred for several different reasons, such as the fact that the temperature control might not have been exactly the same or that my judgement of when the cross may have disappeared might not have been exactly the same for each one.
I did not have any problem whilst carrying out my investigation apart and do not believe I could have done it any better without specialist equipment with plenty of time.
My results do support the first part of my prediction. There were no points on my scatter graph that were not on or close to the line of best fit. I will heat the solution for a few minutes until the desired heat is reached, i. Furthermore, the graph is a perfect curve It is obvious that there is a general trend in the results.
Below is a table to show the effect of changing different variables. The quality of my evidence is good. Tripod Method Firstly I will draw a small dark cross on a piece of paper and place it on a bench mat.
Variables There are different variables which can be changed. In order to provide additional evidence and extend my investigation to find out more and back up my conclusion I could perhaps repeat the experiment using specialist equipment.
Overall I think that my investigation was successful in obtaining reliable results. There are no anomalous results which shows that the experiment was very accurate. I will then put 40cm3 of sodium thiosulphate into a conical flask and place it on a tripod and gauze.
In addition to this, more particles have activation energy. If the results were consistent and accurate I could use them to back up my original theory. As the temperature increases the rate of reaction increases too, due to more collisions and more successful collisions, caused by the increase in temperature.
Below are diagrams to illustrate and explain my method Fair Test To ensure that this experiment is fair I will control the variables, i. Furthermore I will measure out the volumes of both the sodium thiosulphate and hydrochloric acid to the greatest degree of accuracy I can manage.Rates of Reaction.
How can the Rate of the Reaction between Sodium Thiosulfate and dilute Hydrochloric Acid be Measured?. HCl + sodium thiosulfate sodium chloride + sulfur dioxide + sulfur + water.
2HCl (aq) + Na 2 S 2 O 3(aq) 2NaCl (aq) + SO 2(g) + S (s) + H 2 O (l). The rate of this reaction can be measured by looking at the rate at which the. Using a weight balance we measure out 8g of Sodium thiosulphate, that we added too cm³ of water.
We mixed the solution until all the crystals were dissolved. Then you pour 50 cm³, 40 cm³, 30 cm³, 20 cm³, and 10 cm³. The reaction of sodium thiosulfate and hydrochloric acid generates sulfur dioxide gas, which is a skin and eye irritant.
Perform this demonstration in a well-ventilated lab only.
Avoid contact of all chemicals with eyes and skin. Rate Laws, part of the Flinn Scientific—Teaching Chemistry eLearning Video Series. Oct 24, · For my chemistry coursework I am doing the reaction sodium thiosulphate and hydrochloric acid.
I measured the reaction by using a light meter to see how much light got through the beaker, as it got cloudier.
Chemistry Coursework Planning Aim: To find the effect of concentration of thiosulphate on the rate of reaction between sodium thiosulphate and hydrochloric mi-centre.comuction: Word Equation for the reaction: Balanced Symbol Equation for the reaction: Observations during the reaction: • A yellow precipitate of Sulphur starts to form and the reaction mixture.
- Sodium Thiosulphate and Hydrochloric Acid Reaction Investigation Aim To see the effects of concentration on the rate of a reaction between sodium thiosulphate and hydrochloric acid.
Background information The collision theory briefly: For a reaction to occur particles have to collide with each other.Download