Introduction
Over the next few weeks I will be doing several attempts of the same experiment that involves the reaction of sodium thiosulphate and hydrochloric acid, I will be closely watching the reaction and how long in takes for the reactants to react. As yet I have not decided which of the several variables I will be changing. I also aim to take results of the reaction down onto a table, which then will be transferred onto a line graph, which will show us the nature of the reaction.
Variables
There are five factors which affect the rate of a reaction, according to the collision theory: temperature, concentration (of solution), pressure (in gases), surface are (of solid reactants), and catalysts. I have chosen to investigate the effect of temperature on the reactants.
Aim
To see the effects of a change in temperature and concentration we affect the rate of the reaction. The reaction that will be used is:
Sodium Thiosulphate + Hydrochloric Acid
Na2S2O3 (aq) + 2HCl (aq).
Plan
I am going to investigate what happens when sodium thiosulphate and Hydrochloric acid react.
As I have done this experiment before I have a good understanding of what I need to so hopefully nothing will go wrong, also I will be going back to results and information I used before the experiment to make sure I am doing everything right.
As I want to have a fair test, so that I get accurate results, I will make sure that all the main variables will stay the same all the way through the experiment, concentration of both solutions will be kept constant, as there is no gas the variable of pressure wont have an affect on this reaction, as I am using no solids the variable of suface area wont be a problem, and finally as I am not using a catalyst it wont have an effect on the reaction. As well as these things being important there is a more important aspect that I will need to take into account and that is my own safety, and the safety of my fellow pupils. To make sure I don’t endanger myself I will be using the following apparatus:
1 thermometer
1 beaker
2 measuring cylinders
1 conical flask
1 tripod
1 gauze
1 heatproof mat
1 stopwatch
1 Bunsen burner
1 pair of tongs
1 pair of goggles
To make it easy to follow when drawing graphs and when logging my data I will be using a table similar to this: