To investigate the rate of reaction between Sodium Thiosulphate (-Na - _2 S_(2 ) O_3) and Hydrochloric acid (HCl)?

This is the word equation for this reaction:

The reaction can also be expressed as a symbol equation:

Na2S20 3 + 2HCl SO2 + S + H20 + 2NaCl

Apparatus:

1. 2 Measuring cylinders
2. Hydrochloric acid
3. Sodium Thiosulphate
4. Distilled water
5. Piece of paper
6. Pen
7. Stopwatch
8. 2 Test tubes
9. Calorimeter
10. Cuvette
11. Water bath

        Paper with X on it        

Distilled water        Sodium Thio-                2 measuring

        Sulphate                cylinders

        HCl

        

        

Method:

1. Firstly collect all the equipment listed.
2. Then following the table fill up each measuring cylinders with the amount of substance needed.
3. Label each cylinder with the name of the substance you first put in it.
4. Put the chemicals for the time being in a place that will keep the substances at their same temperature.
5. Then pour the Sodium Thiosulphate into the measuring cylinder.
6. Then follow that up by pouring both the HCl and distilled water (if any) at the same time into the cylinder.
7. As soon as you pour them into the measuring cylinder then pour them in the test tubes and start the stopwatch.
8. Keep on observing the test tube until you cannot see the X.
9. As soon as you can’t see the X stop the stopwatch.
10. Record the time you get and carry on the experiment.
11. Once you have got a full table of results draw a graph and repeat the whole experiment again.

Safety:

To make sure that me and my team carry out my experiment safely I will wear firstly goggles throughout the experiment as that is Miss Essiens golden rule. We will keep the equipment safe by elected a team member to protect the equipment so that nothing will break. I will also make sure that the surroundings I am working in are clear. For example, I will move any bags, coats or books out of the way hence I will wash my hand before I make any contact with the equipment and also wash my hands after the experiment has finished.

Fair Test: 

To make my experiment a fair test for each of my solution I had to keep 10ML of Thiosulphate and also when I repeated the test I had to keep the concentrations the same. To make it a fair test I made sure I washed all my equipment with distilled water so that when I repeated the experiment I knew how much I was using.

Preliminary test

In the preliminary we did the experiment at room temperature which is (36-37 degrees) starting at a concentration of 1M. We had to measure out 10ML of Sodium Thiosulphate and 10ML of Hydrochloric Acid. We then poured the Hydrochloric Acid in to the Thiosulphate and then timed how long it takes for the solution to turn cloudy on the X. We did the preliminary so that we know what to do in the upcoming experiments such as the one where the room temperature varies.