Rate of Reaction

TEMPERATURE

Aim:

Aim: To determine how the change in temperature affects the rate of reaction between Sodium Thiosulfate and Hydrochloric acid

Variables

• Independent variable (What we are changing): Temperature of Hydrochloric Acid (Range: 0*C, 20*C, 40*C, 60*C, 80*C)

• Dependent variable (What we measure to record for results): Time take in seconds for cross to visibly disappear (Cross drawn on piece of paper held behind water bath)

Controlled Variables

• Volume of Hydrochloric Acid 2.0 M

• Volume of Sodium Thiosulfate

• Size and position of cross

• Equipment

• Person timing

• Stop watch used to record time

Equipment

• Test tubes• 50mL Beaker• Hydrochloric Acid 2.0 M• Sodium Thiosulfate• Water• Hot water jug• Stop watch• Thermometer• Paper with cross on it• Pen

Method:1. Collect all equipment – Test tubes, 50mL

beaker, Hydrochloric Acid, Sodium Thiosulfate, Stop watch, Thermometer

2. Use hot water jug to boil a beaker full of water3. Fill test tube with 5mL of 2.0 M Hydrochloric

Acid and place in beaker of water to reach water temperature

4. Draw a cross on a piece of paper and place on outside of beaker

5. Measure temperature of Hydrochloric acid, once it has reached 80*C add 5mL of Sodium Thiosulfate. At that point start the timer.

6. Watch the cross through the test tube, once it is not visible stop the timer and record time in table.

7. Clean test tube out and add 5mL of Hydrochloric acid to the test tube, place test tube in beaker.

8. Add some cold water to your hot water beaker to bring the temperature down to 60*C. Once the Hydrochloric acid is 60*C add 5mL of Sodium Thiosulfate.

9. Watch the cross through the test tube, once it is not visible stop the timer and record time in table.

10. Repeat steps8,9 and 10 for a second test with 60*C

11. Repeat steps 8,9, 10 and 11 with Hydrochloric acid at 40*C, 20*C and 0*C

Results Table

Time taken for cross to not be visible through test tube

Temperature of HCl

Test 1 Test 2 Test 3 Average

80*C

60*C

40*C

20*C

0*C

Graph

020406080

100120140160180200

0 20 40 60 80 100

EastWestNorth

How temperature effects rate of reaction between Hydrochloric acid and Sodium Thiosulfate

Tim

e in

se

cond

s

Temperature in Degrees Celsius

Conclusion

• Needs to state what happened in results and how we know that.

• Talk directly about your results– What do your results show?– How did that affect the rate of reaction?– Justify these findings using data

Conclusion

These results show the higher the temperature of the 2.0 Mol Hydrochloric Acid the faster the visibility of the cross disappeared and therefore the faster the rate of reaction. The results show this clearly with the visibility of the cross disappearing in _____seconds at ____________ for the 2.0 M Hydrochloric acid compared to the visibility of the cross disappearing in _______ seconds at __________ for the 2.0 M Hydrochloric acid.

Justification

• Justification: Explanation of why you did what you did during the method– What did you keep constant?– How did you keep that constant?– How did you ensure your test was fair?

Justification

• I used 5 different temperatures of Hydrochloric acid so that I can have accuracy in my data as the more tests I complete the more data I have to review

• 1 only had one reaction going at a time to ensure that I correctly timed the reaction

• I used the same equipment to ensure their were no differences in the measuring

• I was the only one doing the experiment to keep the measuring and timing of the experiment the same.

• I accurately measured the volume of Hydrochloric acid and sodium Thiosulfate so that the volume of acid was not a factor in the investigation.

• We used a water bath to get the temperature of the acid the desired temperature.

• I performed the test quickly and efficiently to make sure the temperature of the acid did not cool down from the temperature I measured.

Discussion

• Relate the finding from your investigation to the particle collision theory of reaction:– As temperature increases what happens to

particles?– How does this affect the rate of reaction?

Discussion

The higher the temperature of Hydrochloric acid the faster the particles are moving in the acid. This means the chance of collision between the two substances is greater, and therefore the higher the change of effective collision. The higher the number of effective collisions between the Hydrochloric acid and the sodium Thiosulfate, the faster the reaction will be completed.

AIM:

Aim: To determine how the change in surface area affects the rate of reaction between calcium carbonate and Hydrocholoric acid.

Use template to design and record investigation of the Aim above

You will have: 1. Pestle and mortars 2. Electronic balance to weigh out the calcium

carbonate