Investigating the effect of Temperature on the reaction between Sodium Thiosuphate and hydrochloric acid

Investigating the effect of Temperature on the reaction between Sodium Thiosuphate and hydrochloric acid

· Planning

I am investigating the different temperatures on the reaction between
Sodium Thiosuphate and Hydrochloric acid.

The factors I could investigate would be temperature, concentration and substances. I have chosen to investigate Temperature.

I predict that the higher the temperature the more rapidly the cross would obscure. This is because the higher the temperature the more often the particles collide and react, when the particles collide more often they would collide harder because they have more energy, making the collisions bigger and faster, the collision success rate is higher. I will make my investigation a fair test by keeping the quantities of the Hydrochloric acid at room temperature and Sodium Thiosuphate heated as accurate as possible. Also make sure the stop clock is started at the same point each time a measurement is taken.

I will carry out the investigation by:

1. Set up the Diagram

2. Put the test tubes of Sodium Thiosuphate into the beaker above the
Bunsen burner

3. Put a thermometer into it

4. Remove the test tube once its reached the desired temperature and pour contence into the empty beaker

5. As you begin to pour the test tube of Hydrochloric Acid contence into the beaker start the stop clock

6. When the cross on the paper becomes obscured stop the clock and record the result

7. Rinse out the beaker where the reaction took place

8. Repeat with five different temperatures, using ice to cool down the
Sodium Thiosuphate, and repeat it all twice.

The equipment I will use is:

· Hydrochloric acid
· Sodium Thiosuphate
· 2 x Measuring cylinders
· 2 x Test tubes
· stop clock
· 2 glass beakers
· 2 thermometers
· Bunsen burner
· water
· tripod
· heat mat
· gauge
· paper with pencil cross

I will make sure my results are accurate by referring to graphs, e.g.: if one point is greatly out of alignment, it should be repeated.

Also I will make sure that the meniscus of the hydrochloric acid and
Thiosuphate is flat and not to one side of the test tube or measuring cylinder. I will take five measurements with a 10 gap interval and I will repeat this twice and take an average to make my results more accurate.

Back ground Research - Trial Experiment

I conducted a trial experiment to find out the correct quantities of sodium thiosulphate and hydrochloric acid for the main experiment. We were aiming for the cross to disappear in around one minute.

We found the more hydrochloric acid the slower the X disappeared.