Finding the Activation Energy Between Hydrochloric Acid an Sodium Thiosulfate
Finding the Activation Energy of the reaction between Hydrochloric Acid and Sodium Thiosulfate
The equation for the reaction is: S2O32- (aq) + 2H+(aq) ⋄ SO2 (g) + S(s) + H2O (l)
Equipment
- 2 boiling tubes
- 400 cm3 beakers
- Marker pen
- Stand and clamp
- Timer
- Bunsen burner, tripod and gauze
- 0 – 100 oC thermometer
- 2 x 10 cm3 measuring cylinders
- Access to a fume cupboard.
Method
1. Label two boiling tubes A and B. Mark a dark spot on the side of a 400cm3 beaker, then ½ fill it with water. Clamp tube A and immerse in the water bath as shown in the diagram above.
2. Using a measuring cylinder, transfer 10cm3 of sodium thiosulfate solution to tube A.
3. Using a clean measuring cylinder, transfer 10cm3 of hydrochloric acid to tube B and place the tube in the beaker of water.
4. Allow both solutions to reach thermal equilibrium with the water in the beaker for a few minutes. 5. Add the solution from tube B to that in tube A, starting a timer as you do so. Mix the solution in A by gently stirring using the thermometer. Read and record the temperature.
6. Observe the spot on the side of the beaker by looking at it through the solution in A. Record the time at which the spot can no longer be seen due to it becoming obscured by the sulphur precipitate formed in A.
7. Dispose of the mixture in tube A as directed. Rinse out tube and wash and dry the thermometer. 8. Using a Bunsen burner to gently heat the water bath, and/or use ice to cool the water bath repeat steps 2 – 7 until you have 5 sets of results at five different temperatures. The first will be at room temperature and the other four evenly spaced between zero degrees celcius and about 50oC (try not to exceed this temperature). 9. Record your results in a suitable manner.
Processing Data
To work out Average Time: Add all trail results for one specific temperature together and divide by the number of trials done for this drop height (in this case 3 for every temperature)
eg. the
The equation for the reaction is: S2O32- (aq) + 2H+(aq) ⋄ SO2 (g) + S(s) + H2O (l)
Equipment
- 2 boiling tubes
- 400 cm3 beakers
- Marker pen
- Stand and clamp
- Timer
- Bunsen burner, tripod and gauze
- 0 – 100 oC thermometer
- 2 x 10 cm3 measuring cylinders
- Access to a fume cupboard.
Method
1. Label two boiling tubes A and B. Mark a dark spot on the side of a 400cm3 beaker, then ½ fill it with water. Clamp tube A and immerse in the water bath as shown in the diagram above.
2. Using a measuring cylinder, transfer 10cm3 of sodium thiosulfate solution to tube A.
3. Using a clean measuring cylinder, transfer 10cm3 of hydrochloric acid to tube B and place the tube in the beaker of water.
4. Allow both solutions to reach thermal equilibrium with the water in the beaker for a few minutes. 5. Add the solution from tube B to that in tube A, starting a timer as you do so. Mix the solution in A by gently stirring using the thermometer. Read and record the temperature.
6. Observe the spot on the side of the beaker by looking at it through the solution in A. Record the time at which the spot can no longer be seen due to it becoming obscured by the sulphur precipitate formed in A.
7. Dispose of the mixture in tube A as directed. Rinse out tube and wash and dry the thermometer. 8. Using a Bunsen burner to gently heat the water bath, and/or use ice to cool the water bath repeat steps 2 – 7 until you have 5 sets of results at five different temperatures. The first will be at room temperature and the other four evenly spaced between zero degrees celcius and about 50oC (try not to exceed this temperature). 9. Record your results in a suitable manner.
Processing Data
To work out Average Time: Add all trail results for one specific temperature together and divide by the number of trials done for this drop height (in this case 3 for every temperature)
eg. the