Graphs All of the graphs that I drew for this investigation show a negative correlation. This shows that my data is quite accurate. For example, when my concentration was 1M the average reaction time was seconds, and then when the concentration was 5M the average reaction time was seconds. This makes sure that my experiment runs smoothly. This shows that there is a difference in the data which proves accuracy.
I could have use a colorimeter to identify colour changes in the products. The points in the top right are quite far down so this shows a negative correlation. My conclusion is justifiable because I have backed it up with points from my data and I have proved all the points that I made. I drew 6 different graphs for this investigation. Sorry, but copying text is forbidden on this website! The enthalpy change is the amount of heat absorbed or released when a chemical reaction occurs at a constant pressure. Accessed May 23,
Rate of Reaction – Sodium Thiosulphate and Hydrochloric Acid Coursework
There are a few mild outliers. This hyddochloric gives the reactant particles enough energy to courseworj with enough force to break apart the bonds so that new products can be made from atoms. This is because the rate is determined by the rate of the slowest step of the mechanism, known as the rate determining step.
This is good because I will instantly be able to see any change in the solution. If I was using solids, I could investigate surface area and for gases I could investigate pressure In concentration I looked at five different hycrochloric of HCl The volume of HCl stayed the same; also the volume of sodium thiosulphate stayed the same, the concentration of sodium thiosulphate stayed the same.
Leave your email and we will send you an example after 24 hours Sorry, but copying text is forbidden on this website! Start by making the concentrations, using a graduated pipette measure out the correct volumes of Sodium Thiosulphate and put into 5 small 50cm3 beakers.
Sodium Thiosulphate + Hydrochloric Acid Coursework – GCSE Science – Marked by
Thiozulphate will be changing this variable and seeing how it affect the time taken for the reaction to take place and therefore how the concentration affects the rate of the reaction. Another limitation of the procedure at the start of the timing and I had to add the chemicals together and start the stopwatch. As well as environmental variations in temperature the reaction was exothermic and heat is produced. To control this the same volumes will be used and the same conical flask will be used and therefore the depth will be the same.
Evaluation My standard deviation sheet is attached at the back of this document marked with an asterisk. I did, however find some outliers in my results. I wrote down my results and then moved on to the next concentration of sodium thiosulphate.
Sorry, but copying text is not allowed on this site. Hyddochloric care with glass wear, such as pipettes as they are fragile and may break easily.
Click to learn more https: It can also be found in the stomach. Variables An independent variable is one that is controlled by me, for example; the thiosulpnate, the time limit and mixing speed.
Another error is in the variation of temperature. I would also consider using a wider range of concentrations so I can do in-depth analysis and I can compare the two acids.
Background Research Chemical reactions are to do with changing the thiosulphage that form the base of your experiment.
However as only one variable can be changed I will keep one reactant constant whilst changing the other to get a fair xoursework of results. This shows that as you increase the independent variable the concentrationthe other variable the time taken for the experimentwent down.
Sodium Thiosulphate and Hydrochloric Acid Coursework Essay
These graphs show how if the time taken coursrwork the reaction to reach a specific concentration is too long it will not be a true reflection on the actual initial rate of the reaction. This good because it shows that for every increase in concentration is a decrease in rate of reaction.
This is the reaction I will be considering: In this reaction although 2HCl molecules are needed for the reaction to take place; however from the kinetics that I found HCl has no effect on the rate and is zero order.
Another method that could be used is to measure the products formed.
Instead of using the cross method I would use a light intensity machine that could measure the change in colour over a period of time and stop and start timing when it had reach a certain value.
When the temperature increases the k constant will increase, this is because the molecules have more kinetic energy and there is a higher probability that they will collide and react.
However the overall order for the reaction cannot be calculated using the stoichiometry in the overall equation. I did have some outliers in my results; however I think that the experiment went fairly well overall. The enthalpy change is the amount of heat absorbed or released when a chemical hyrrochloric occurs at a constant pressure.