1. El Legado de Un Nguyen
Welcome 3 2 1

2. What is the effect of reactant particle size on the rate of a chemical reaction?
By: An Nguyen

3. Research Facts
In order for a chemical reaction to occur, the particles, atoms or ions, which are REACTANTS, must physically come into contact with one another. Anything that increases the frequency of these encounters will increase the rate at which PRODUCTS are formed.
The rate of a chemical reaction can be increased by increasing the temperature of these reactants.
If any of the products or reactants involved in a chemical reaction are gases, the rate of reaction will decrease as pressure on the system is increased.
As more surface area are expose the rate chemical reaction increases
When water reacts with Alka-Seltzer, one of the products of the reaction is carbon dioxide gas.
When two substances react together, they can form new chemicals or products. In this chemical reaction, the vinegar and baking soda react and create carbon dioxide. It is these bubbles of gas that inflate the balloon. 01
Bayer HealthCare. "Alka-Seltzer Plus - Student Science Experiments." Alka-Seltzer -- Alka Seltzer Plus. Bayer, Web. 01 Dec <
Wilbraham, Antony C., and Dennis D. Staley. Pearson Chemistry. Boston, MA: Pearson, Print.
HowStuffWorks, Inc. "HowStuffWorks "Why Does Alka Seltzer Fizz?"" HowStuffWorks "Science" Web. 01 Dec <

4. Introduction and Background
A chemical reaction is a process, in which one or more substances (reactants) are chemically changed into one or more new substances (products,) this also causes a change in the composition in the valence electrons. In this experiment, Alka-Seltzer will be used to demonstrate the chemical reaction in which the rate of CO2 production will be measured. The main ingredients of Alka-Seltzer tablets are aspirin, citric acid, and sodium bicarbonate (NaHCO3). When sodium bicarbonate dissolves in water, it dissociates (splits apart) into sodium (Na+) and bicarbonate (HCO3−) ions. The bicarbonate reacts with hydrogen ions (H+) from the citric acid to form carbon dioxide and water. The reaction is described by the following chemical equation:
The purpose of this experiment is to determine if changes reactant particle size will effects on the rate of a chemical reaction.
The experimenter predicts that as the reactant particles are smaller, the chemical reaction rate will be faster. 01

5. 01 Experimental Design Diagram
Title: What is the effect of reactant particle size on the rate of a chemical reaction?
Hypothesis: If the reactant size particles are smaller, then it will react faster.
Independent Variable: Different Reactant Size Particles
Particle Size
Whole Tablet
Tablet Broken in Half
Tablet Broken in Quarters
Powdered Tablets
Trials 3
Dependent Variable: Rate of Chemical Reaction (sec)
Controlled Variables (constants): Same amount of water (mL)
Same amount of temperature
Same type of reactant
Same type of water 01

6. Materials and Equipment
At least 12 Alka-Seltzer® tablets
Sheet of blank paper
Hammer
Piece of scrap wood
Thermometer (-10°C to 110°C)
Clear 12 ounce (355 mL) drinking glass (or larger)
Note: Use Pyrex glass when working with water heated on the stove or in the microwave
Measuring cup
Masking tape
Stirring rod
Tap water
Stop watch
Lab notebook
Pencil
Knife
A helper
***Safety Considerations:
None are needed, because the reactant use in this experiment is very stable.
Safety Equipment
Goggle
Gloves
Apron

7. Procedures

9. How Does Reactant Particle Size Affect the Rate of Chemical Reaction?
DV: Rate of Chemical Reaction (sec)
IV:
Trial 1
Trial 2
Trial 3
Mean/Ave
Whole Tablet
55.2
49.1 48
50.8
Tablet Broken into Half
48.5
47.6
48.2
48.1
Tablet Broken into Quarters
41.4
42.3
42.6
42.1
Clear(control)
31.3
32.4
30.9
31.5 01
*The recorded data was the total reaction rate of different reactant particle when react with H2O molecules. The rates were measured in seconds.

10. Data Analysis 01

11. As the reactant (Alka-Seltzer) are broken into smaller particles (powdered tablet) the rate of reaction increases, the rate of chemical reaction for smaller particle (powdered tablet) are faster or quicker than the rate of bigger particles (whole tablet); when the small particle react with water it the rate seem to increase the most, its final rate of reaction that were recorded are the smaller particles (powdered tablet) have a faster rate of chemical reaction than other bigger particles ( a whole tablet, a tablet broken in half, and a tablet broken in quarters.)
After twelve trials, the average, or mean, of chemical reaction (seconds) was calculated to observe the changes that happen. When whole tablets of Alka-Seltzer, were but into water, it mean or average of the chemical reaction rate is /- seconds; when tablets of Alka-Seltzer are broken in half, were but into the water, it mean or average of the chemical reaction rate is /- seconds; when tablets of Alka-Seltzer are broken into quarters, were but into water, the mean or average of the chemical reaction rate is /- seconds; and when tablets of Alka-Seltzer are broken into quarters, were but into water, the mean or average of the chemical reaction rate is /- seconds. The independent variable is the different reactant size particles; the dependent variable is the rate of chemical reactions measured in seconds. Powdered particle of Alka-Seltzer has the fastest rate of chemical reaction, next are the broken into quarter tablet of Alka-Seltzer, then the broken in half tablet of Alka-Seltzer and last the whole tablet of Alka-Seltzer. Note that each different size particles was tested in the total of three trials.

12. The Experiment

13. Experiment The Fizz

14. Let The Rate Increase!

15. Conclusion
The purpose of this experiment is to determine if changes reactant particle size will effects on the rate of a chemical reaction. As powdered tablet react with water, the rate of reaction are increases and take less time, which were supported by the recorded data. The central tendency of this data is measure by the mean. The mean for whole tablet of Alka-Seltzer after three trials is /- seconds; the mean for the tablet of Alka-Seltzer broken into half after three trails is /- seconds; the mean for the tablet of Alka-Seltzer broken into quarters after three trials is /- seconds; and the mean for the powdered tablet of Alka-Seltzer after three trials is /- seconds.
The data did support my hypothesis, which was as the reactant particles are smaller (powdered tablet), the rate of chemical reaction will be faster. I may not have been able to accurately observe changes because thermometers are not always accurate. Temperature of the water and the glass are other factors that may also affected it, and so the measurement may not be so accurately measured.

16. Conclusion
According to the data, the powdered tablet has the fastest rate of chemical reaction, which means tablets broken into quarters, tablets broken into half and whole tablet would not so much improve the rate of chemical reaction.
For further studies, I suggest having more trials because when it comes to dissolving reactant, sometime the tablet may not have the same amount of concentrated particle in it. So with more trails for the experiment, there would be more confidence in the data.

17. Work Cited
Olson, Andrew. "Big Pieces or Small Pieces: Which React Faster?" Science Fair Project
Ideas, Answers, & Tools. 14 May Web. 18 Oct < projects/project_ideas/Chem_p028.shtml?fave=no>.
Orphardt, Charles E. "Chemical Properties." Elmhurst College: Elmhurst, Illinois
Web. 18 Oct <
Anissimov, Michael. "What Are Chemical Reactions?" WiseGEEK: Clear Answers for
Common Questions Web. 18 Oct <
Aberdeen, Stan. "How to Identify the 6 Types of Chemical Reactions | EHow.com."
EHow | How to Videos, Articles & More - Discover the Expert in You. | EHow.com Web. 18 Oct <
Miller, Kenneth R., and Joseph S. Levine. Prentice Hall Biology. Upper Saddle River,
NJ: Pearson Prentice Hall, Print.