How Does Temperature and Particle Size Affect Alka-Seltzer Reaction Rates?

[Juicyfruit11]

Part I: Temperature and Reaction RatesMaterials

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Three Alka-Seltzer tablets
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Water
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Three coffee cups
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Ice
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Thermometer
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Watch with seconds

Procedure:

1.

Chill some water with the ice.
2.

Pour just the water into one coffee cup.
3.

Heat some water and place it in a second coffee cup.
4.

Put room temperature water into the third cup.
Use the thermometer to record, in a data table, the temperature of the water in each cup.
5.

Simultaneously (get help from another person), add one full Alka-Seltzer tablet to each cup and begin timing with your watch.
6.

Record the amount of time needed for each reaction to reach conclusion (stops fizzing).
7.

Graph your results.
*Part II: Particle Size and Reaction Rates

Using mathematics, it is possible to compare the surface area of an object to its volume and get a ratio. Interestingly, if you crush a tablet, the ratio of surface area to volume will be higher in the smaller particles than with the whole tablet.Materials

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Three Alka-Seltzer tablets
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Water
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Spoon
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Three coffee cups
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Watch with seconds

Procedure

1. On a piece of paper, grind up one tablet with the back of the spoon until it is a fine powder.

2. On a second piece of paper, chop one tablet into several small pieces but do not grind it.

3. Fill the three cups with the same amount of water
Note: the water should be approximately the same temperature at the start.

4. Simultaneously (again, get help), add the ground tablet to one cup, the chopped tablet to a second cup, and the whole tablet to the third cup. Begin timing with your watch.

5. Record the amount of time needed for each reaction to reach conclusion (to stop fizzing).

6. Graph your results.
Note: On the Y axis = time of reaction; on X axis where you are putting "surface area exposed" use 1 = for whole tablets; 5 for small pieces; 10 for crushed.Analysis

You will submit these analysis questions and your two graphs! Make sure you include your data and two graphs.

1. What differences did you observe in the reactions in the three cups in Part I?

2. Look at your graph of temperature vs. reaction time. Describe this graph in mathematical terms—e.g., linear, parabolic (curved up).

3. As temperature increases, what happens to reaction time?

4. What differences did you observe in the reactions in the three cups in Part II?

5. Look at your graph of surface area vs. reaction time. Describe this graph in mathematical terms.

6. As surface area increases (smaller particles), what happens to reaction time?

7. Based on your data, under what conditions would you expect the reaction between baking soda and vinegar to occur most quickly?

Alright, I don't have any way to get Alka Seltzer in the next couple of days, so I wouldn't be able to do this experiment. Any ideas on what will happen in each experiment?

 

[lalbatros]

you can try with any other kind of effervescent tablets

 

[ravenprp]

Based on the materials and procedures provided, here are some predictions for the Alka Seltzer experiment:

Part I: Temperature and Reaction Rates
- The Alka Seltzer tablet in the cup with the chilled water will have the slowest reaction time, as colder temperatures typically slow down chemical reactions.
- The Alka Seltzer tablet in the cup with the heated water will have the fastest reaction time, as warmer temperatures typically speed up chemical reactions.
- The Alka Seltzer tablet in the cup with room temperature water will have a reaction time somewhere in between the other two cups.

Part II: Particle Size and Reaction Rates
- The Alka Seltzer tablet in the cup with the ground up powder will have the fastest reaction time, as the increased surface area will allow for more contact between the tablet and the water.
- The Alka Seltzer tablet in the cup with the chopped pieces will have a slightly slower reaction time than the ground up powder, but still faster than the whole tablet.
- The Alka Seltzer tablet in the cup with the whole tablet will have the slowest reaction time, as there is less surface area for the water to interact with.

Overall, it is expected that the warmer temperature and smaller particle size will result in faster reaction times, while colder temperature and larger particle size will result in slower reaction times. Additionally, the graph for temperature vs. reaction time is expected to show a parabolic (curved up) relationship, while the graph for surface area vs. reaction time is expected to show a linear relationship.