Now it is time to design your own experiment to test how particle size (or surface area) affects reaction rate. Answer the next seven questions about your experiment that tests the effect of particle size on reaction rate.
1) What would you do next if your results did not support your hypothesis? Hint: What might be sources of error in your experiment?
The hypothesis: The smaller the particle size (or larger the surface area), the faster the reaction rate will be. This is because smaller particles (or larger surface area) will have more exposed reactive sites allowing for more collisions with other particles, leading to a higher reaction rate.
Hint: You are welcome to use the alka seltzer tablet and water reaction again to design this experiment that tests the effect of particle size on reaction rate. You are not required to use the alka seltzer experiment, you could design a different experiment but it must test particle size affect on reaction rate.
If the results did not support the hypothesis, the next step would be to identify sources of error in the experiment. Possible sources of error could include inaccuracies in measuring the size of the particles, variations in the temperature or pressure of the reaction, or human error in timing the reaction. The experiment may need to be repeated with adjustments made to the procedure or apparatus to reduce sources of error and increase accuracy. Additionally, it may be necessary to compare the results to previous studies on the topic or consult a scientific expert for possible explanations and solutions.
If the results of the experiment did not support the hypothesis, there are several potential sources of error that could have affected the outcome. In such a case, the following steps could be taken:
1) Review the experimental procedure: Carefully examine the steps performed during the experiment to check for any procedural errors or inconsistencies that may have influenced the results.
2) Assess the variables: Verify that all variables, including particle size, concentration, temperature, and reaction time, were controlled and kept constant throughout the experiment. Any variations in these variables could have affected the reaction rate.
3) Consider the accuracy of measurements: Double-check the accuracy of measurements made during the experiment, such as recording the time it took for the reaction to occur. Inaccurate measurements could lead to incorrect interpretation of the results.
4) Evaluate the sample size: If the sample size used in the experiment was too small, it may not have provided statistically significant results. Consider increasing the number of trials or replicating the experiment to obtain a larger sample size.
5) Examine the particles used: Confirm that the particles used in the experiment were of consistent size and composition. Variations in particle size or impurities could have affected the reaction rate.
6) Analyze potential sources of contamination: Check for possible sources of contamination in the experimental setup that might have influenced the results. For instance, if the containers used to mix the reactants were not properly cleaned, residual substances could have affected the reaction rate.
7) Repeat the experiment with modified conditions: If any discrepancies or errors are identified, modify the experimental conditions accordingly and repeat the experiment to see if the results align with the hypothesis.
By conducting a thorough analysis of the experiment and addressing potential sources of error, it will be possible to identify whether adjustments need to be made and if further investigation is required.