Lab 6-2: FACTORS AFFECTING REACTION RATE By: Suzan Ozgur
Purpose:
To understand the different factors that affect the rate of a chemical reaction; the
effect of Temperature, Concentration, Surface Area, and the Presence of a Catalyst.
Part 1: Effect of Temperature
Purpose:
To understand how temperature affects the rate at which the Alka Seltzer tablet dissolves.
Hypothesis:
If the rate at which the Alka Seltzer tablet dissolves is related to the temperature, then the temperature will affect the rate at which the tablet dissolves.
Independent Variable: Temperature
Dependent Variable: Alka Seltzer
Controlled Variables: Amount of water, degree of temperature, amount of tablets
Materials:
- Water (250ml)
- 1 Hot Plate
- 3 Alka Seltzer Tablet
- 1 Glass Beaker (500mL)
- 1 Graduated Cylinder (50mL)
- 1 Thermometer
- 1 Timer
- 1 Pair of Tongs
- 1 Beaker of Ice (125 mL)
Procedure:
1. Measure 250 ml of water using a graduated cylinder, and pour it into a 500ml beaker.
2. Scoop out 125ml of ice, and add it into the beaker of water.
3. Take the temperature of the water, and record it.
4. Place the Alka Seltzer tablet into the beaker carefully.
5. Time how long it takes the tablet to dissolve completely. Observe and record observations.
6. Follow your teacher's instructions for disposal of wastes
7. Measure 250 ml of water using a graduated cylinder, and pour it into a 500ml beaker.
8. Use your tongs to grab the beaker, and place it on the hot plate for about 40 seconds.
9. Repeat steps 3-5
10. Clean up, and put away the equipment you have used.
Part 2: Effect of Concentration
Purpose:
To understand how concentration affects the rate at which a piece of zinc dissolves.
Hypothesis:
If the rate at which zinc will dissolve is related to the concentration of Hydrochloric acid (HCl) then the concentration of HCl will affect the rate at which the zinc will dissolve.
Independent Variable: Concentration of Hydrochloric Acid
Dependent Variable: Rate at which zinc will dissolve
Controlled Variables: Amount of Hydrochloric Solution, amount of zinc metal
Materials:
- Hydrochloric acid solutions (0.1M, 1.0M, and 2.0M)
- 3 Test Tubes
- 3 Strips of Zinc Metal
- 1 Funnel
- Graduated Cylinder (200mL)
- 1 Pair of Gloves
- 1 Pair of Safety Goggles
- 1 Timer
Procedure:
1. Use a 200mL graduated cylinder to measure 5mL of a 0.1M, 1.0M, and 2.0M.
2. Label each test tube as 0.1M, 1.0M, and 2.0M
3. Funnel each solution into its correct test tube.
4. Carefully, drop one zinc metal into each test tube, and observe. Record your observations.
5. Clean up and put away the equipment you have used.
Part 3: Effect of Surface Area
Purpose:
To understand the effect of different surface areas, and how they affect the rate at which an Alka Seltzer tablet dissolves.
Hypothesis:
If the rate at which the Alka Seltzer tablet dissolves is related to the surface area, then the surface area will affect the rate at which the Alks Seltzer tablet dissolves.
Independent Variable: Surface Area
Dependent Variable: Alka Seltzer
Controlled Variables: Amount of water, number of Alka Seltzer tablets
Materials:
- 3 Alka Seltzer Tablets (whole, chunks, & crushed)
- Water (150mL)
- 1Beaker (500mL)
- 1 Timer
- 1 Pestle Mortar
Procedure:
1. Fill the beaker with 150mL of water.
2. Place the whole Alka Seltzer tablet into the beaker.
3. Time the reaction, and record your observations.
4. Repeat steps 1-3, instead with a crushed tablet and a chunked tablet.
5. Clean up and put away the equipment you have used.
Purpose:
To understand the effect of different surface areas, and how they affect the rate at which an Alka Seltzer tablet dissolves.
Hypothesis:
If the rate at which the Alka Seltzer tablet dissolves is related to the surface area, then the surface area will affect the rate at which the Alks Seltzer tablet dissolves.
Independent Variable: Surface Area
Dependent Variable: Alka Seltzer
Controlled Variables: Amount of water, number of Alka Seltzer tablets
Materials:
- 3 Alka Seltzer Tablets (whole, chunks, & crushed)
- Water (150mL)
- 1Beaker (500mL)
- 1 Timer
- 1 Pestle Mortar
Procedure:
1. Fill the beaker with 150mL of water.
2. Place the whole Alka Seltzer tablet into the beaker.
3. Time the reaction, and record your observations.
4. Repeat steps 1-3, instead with a crushed tablet and a chunked tablet.
5. Clean up and put away the equipment you have used.
Part 4: Effect of the Presence of a Catalyst
Purpose:
To understand the effect of the catalyst and how it affects the rate at which the hydrogen peroxide.
Hypothesis:
If the rate at which hydrogen peroxide decomposes is related to the catalyst, then the catalyst will affect the rate at which hydrogen peroxide decomposes.
Independent Variable: Catalyst
Dependent Variable: Hydrogen Peroxide
Controlled Variables: Type of dish soap, amount of hydrogen peroxide, level of temperature
Materials:
- Hydrogen Peroxide (3mL)
-Solid CuCl2
- Solid NaCl
- Solid KI
- Dish Soap
- 3 Test Tubes (500mL)
- Safety Goggles
- Funnel
Procedure:
1. Use a funnel and fill a 500mL test tube with 3mL of hydrogen peroxide. Add a drop of dish soap.
2. Place the solid CuCl2 into the test tube.
3. Repeat steps 1-3 with solid NaCl and KI.
4. Record and observe your results.
5. Clean up and put away the equipment you have used.
Data/Observations
lab_6-2_suzan.xlsx | |
File Size: | 16 kb |
File Type: | xlsx |
lab_6-2.docx | |
File Size: | 12 kb |
File Type: | docx |
Discussion
Part 1: Effect of Temperature
In my hypothesis I stated that: If the rate at which the Alka seltzer tablet dissolves is related to the temperature, then the temperature will affect the rate at which the tablet dissolves. The results conducted from this experiment proved that my hypothesis was valid. When there is an increase in temperature the particles of the reactants will move quickly, which will cause the particles to collide with one another with more energy and more often. Therefore, the higher the temperature, the larger the rate of reaction.
When there is a decrease in temperature the rate of reaction decreases. In this case, the particles will have less energy, which will prevent the particles to move quickly and collide with one another.
In this experiment I observed how three different temperatures of water (cold, warm and hot) affected the rate at which an Alka Seltzer tablet dissolves. I used the different temperatures of water to prove how temperature has a huge effect on the rate of reaction, and how increasing the rate of reaction will increase the speed at which the Alka Seltzer tablet will dissolve. In other words, by placing the tablet in hot water the reactant particles will have more energy and will collide with one another, which will increase the rate of reaction and speed up the time it takes the Alka Seltzer tablet to dissolve. By placing the tablet in cold water, the reactant particles will move slowly, colliding less often and with less energy. Thus, the rate of reaction will decrease, and it will take a longer time for the Alka Seltzer tablet to dissolve. During this experiment, all the variables were considered, identified and controlled. The independent variable was the temperature, the dependent variable was the Alka Seltzer, and the controlled variables were the amount of water, degree of temperature, and the amount of tablets.
The data table for this experiment contains the results that prove how the different temperature levels affect the rate of reaction. The observations prove that a lower temperature does decrease the rate of reaction, and that a higher reaction rate occurs when the temperature increases. The data table shows that when the temperature of the water was 9°C it took 144 seconds for the Alka Seltzer tablet to dissolve. While, when the temperature increased to 51°C the reaction took only 32 seconds, and it took only 25 seconds for the tablet to fully dissolve in 80°C water. Thus, the results gathered during the experiment compared to the theoretical values and results expected.
All in all, the experiment Effect of Temperature was valid and quite successful. I believe that if I were to conduct this experiment again, there would be a few things that I would change. For instance, I would
conduct another trial for each section. I would like to see if the results would vary in anyway. After completing this experiment, I believe that there were no major problems indentified. If I were to repeat this project I would like to test different temperature rates, and even other materials to dissolve.
Part 2: Effect of Concentration
In my hypothesis I stated that: If the rate at which zinc will dissolve is related to the concentration of
Hydrochloric acid (HCl) then the concentration of HCl will affect the rate at which the zinc will dissolve.
The results conducted from this experiment proved that my hypothesis was valid. Since concentration means how much solute is dissolved in a solution, the higher the concentration of reactant particles in a solution;the higher the chance of collisions to occur. Thus, the more collisions that occur, results in a higher
reaction rate. When there is a lower concentration there is a lower rate of reaction, since there is a less chance for a collision to occur among the particles.
In this experiment I observed how three different concentration of HCl (0.01M, 1.0M and 2.0M) affected the rate at which a piece of zinc metal dissolves. I used the three different concentration levels of HCl to prove how increasing the concentration of the reactants results in a higher reaction rate. In other words, by placing zinc metal in higher concentration of HCl solution, there will be more reactant particles to collide with, and the more collisions result with a greater reaction rate; the zinc metal will dissolve quickly. By placing the zinc metal in a lower concentration of HCl will result with fewer collisions to happen because of the lack of particles present. Thus, the rate of reaction will decrease, and it will take a longer time for the zinc metal to dissolve. During this experiment, all the variables were considered, identified, and controlled.
The independent variable was the concentration of Hydrochloric Acid .The dependent variable was the rate at which zinc will dissolve. The controlled variables were the amount of hydrochloric solution, and the amount of zinc metal.
The data table for this experiment contains the results that prove how the different concentrations of HCl affect the rate of reaction. The observations prove that a lower concentration of HCl does decrease the rate of reaction, and that a higher reaction rate occurs when the concentration levels increase. The data table show that when the concentration of HCl was 0.01M the zinc metal did not dissolve; no chemical reaction took place. While, when the concentration increased to 1.0M it took the zinc metal to fully dissolve in 34 minutes, and it took only 17 minutes for the zinc metal to dissolve in 2.0M. Thus, the results gathered during the experiment compared to the theoretical values, and results expected.
When all is said and done, the experiment Effect of Concentration was valid and quite successful. I believe that if I were to perform this experiment again, there would be some things that I would change. For example, I would like to try this lab with different concentration levels of HCl, and observe the outcome of the new factors. After completing this project, I believe that there were no major problems that occurred during the lab. If I were to repeat this project I would like to test how much faster the zinc metal dissolves compared to another type of metal i.e. (silver, gold and lead).
Part 3: Effect of Surface Area
In my hypothesis I stated that: If the rate at which the Alka Seltzer tablet
dissolves is related to the surface area, then the surface area will affect the
rate at which the Alka Seltzer tablet dissolves. The results
conducted from this experiment proved that my hypothesis was valid. Since
surface area is defined as the measure of how much area of an object is
exposed, the more surface contact between the reactants, the higher the rate of
reaction. The less surface contact, the lower the rate of reaction.
In this experiment I observed how three different surface areas of an Alka Seltzer tablet (whole tablet, chunks and crushed) affected the rate at which an Alka Seltzer tablet dissolves. I used the different surface areas of the tablet to prove how surface area has an effect on the rate of reaction, and how increasing the rate of reaction will increase the speed at which the Alka Seltzer tablet will dissolve. In other words, by placing a crushed tablet in a beaker of water, there will be more surface contact between the tablet and the water, which will result in a higher reaction rate. Thus, the tablet will dissolve quickly. During this experiment, all the variables were considered, identified, and controlled. The independent variable was the surface area. The dependent variable was the Alka Seltzer. The controlled variables were the amount of water, and the number of Alka Seltzer tablets.
The data table for this experiment contains the results that prove how the different surface areas of an Alka Seltzer tablet affect the rate of reaction. The observations prove that less surface area contact between the reactants does decrease the rate of reaction, and that a higher reaction rate occurs when the surface contact increases. The data table shows that when a whole tablet was placed into a beaker of water it took 90 seconds for the tablet to fully dissolve, since a whole tablet has less surface contact with the water, compared to the relationship between a crushed tablet. When chunks of Alka Seltzer were placed in the water, the surface contact increased, and it only took 79 seconds for the tablet to dissolve. Lastly, the crushed tablet had the most surface area, and dissolved in 53 seconds. Thus, the results gathered during the lab compared to the theoretical values, and results expected.
At the end of the day, the lab Effect of Surface Area was valid and very successful. I believe that if I were to do this project again I would change one thing; I would use a different material instead of using an Alka Seltzer. After completing this experiment, I believe that there were no major problems indentified. If I were to do this lab again, I would like to use an acidic and basic solution to see if the results would change in any way.
Part 4: Effect of the Presence of a Catalyst
In my hypothesis I stated that: If the rate at which hydrogen peroxide decomposes is related to the catalyst, then the catalyst will affect the rate at which hydrogen peroxide decomposes. The results conducted from this experiment proved that my hypothesis was valid. Since a catalyst is defined as a substance that speeds up the rate of a chemical reaction without being used up in the reaction itself, a chemical reaction with no catalyst would have a lower rate of chemical reaction, compared to a reaction with a catalyst.
In this experiment I observed how a catalyst (nothing, CuCl2, NaCl and KI) affect the rate at which hydrogen peroxide decomposes. By adding a "strong" catalyst to the hydrogen peroxide solution, less energy would be needed to breakdown the hydrogen peroxide. During this experiment, all the variables were considered, identified, and controlled. The independent variable was the catalyst. The dependent variable was the hydrogen peroxide. The controlled variables were the type of dish soap, amount of hydrogen peroxide, and the level of temperature.
The data table for this experiment contains the results that prove the effects a catalyst has on the rate of reaction. The observations prove that the best catalyst was CuCl2 and KI. CuCl2 created a very rapid reaction, while KI had a slower reaction period, but lasted longer. However, both catalysts decomposed the hydrogen peroxide. On the other hand, NaCl (a salt) and “nothing” produced no reaction.
All in all, the lab Effect of the Presence of a Catalyst was valid and quite successful. I believe there are a few things I would change. For instance, I would conduct more than one trail in order to have more accurate lab. After completing this experiment, I believe that there were no major problems indentified. If I were to conduct this experiment again I would like to test more catalysts and compare the results.
In this experiment I observed how three different surface areas of an Alka Seltzer tablet (whole tablet, chunks and crushed) affected the rate at which an Alka Seltzer tablet dissolves. I used the different surface areas of the tablet to prove how surface area has an effect on the rate of reaction, and how increasing the rate of reaction will increase the speed at which the Alka Seltzer tablet will dissolve. In other words, by placing a crushed tablet in a beaker of water, there will be more surface contact between the tablet and the water, which will result in a higher reaction rate. Thus, the tablet will dissolve quickly. During this experiment, all the variables were considered, identified, and controlled. The independent variable was the surface area. The dependent variable was the Alka Seltzer. The controlled variables were the amount of water, and the number of Alka Seltzer tablets.
The data table for this experiment contains the results that prove how the different surface areas of an Alka Seltzer tablet affect the rate of reaction. The observations prove that less surface area contact between the reactants does decrease the rate of reaction, and that a higher reaction rate occurs when the surface contact increases. The data table shows that when a whole tablet was placed into a beaker of water it took 90 seconds for the tablet to fully dissolve, since a whole tablet has less surface contact with the water, compared to the relationship between a crushed tablet. When chunks of Alka Seltzer were placed in the water, the surface contact increased, and it only took 79 seconds for the tablet to dissolve. Lastly, the crushed tablet had the most surface area, and dissolved in 53 seconds. Thus, the results gathered during the lab compared to the theoretical values, and results expected.
At the end of the day, the lab Effect of Surface Area was valid and very successful. I believe that if I were to do this project again I would change one thing; I would use a different material instead of using an Alka Seltzer. After completing this experiment, I believe that there were no major problems indentified. If I were to do this lab again, I would like to use an acidic and basic solution to see if the results would change in any way.
Part 4: Effect of the Presence of a Catalyst
In my hypothesis I stated that: If the rate at which hydrogen peroxide decomposes is related to the catalyst, then the catalyst will affect the rate at which hydrogen peroxide decomposes. The results conducted from this experiment proved that my hypothesis was valid. Since a catalyst is defined as a substance that speeds up the rate of a chemical reaction without being used up in the reaction itself, a chemical reaction with no catalyst would have a lower rate of chemical reaction, compared to a reaction with a catalyst.
In this experiment I observed how a catalyst (nothing, CuCl2, NaCl and KI) affect the rate at which hydrogen peroxide decomposes. By adding a "strong" catalyst to the hydrogen peroxide solution, less energy would be needed to breakdown the hydrogen peroxide. During this experiment, all the variables were considered, identified, and controlled. The independent variable was the catalyst. The dependent variable was the hydrogen peroxide. The controlled variables were the type of dish soap, amount of hydrogen peroxide, and the level of temperature.
The data table for this experiment contains the results that prove the effects a catalyst has on the rate of reaction. The observations prove that the best catalyst was CuCl2 and KI. CuCl2 created a very rapid reaction, while KI had a slower reaction period, but lasted longer. However, both catalysts decomposed the hydrogen peroxide. On the other hand, NaCl (a salt) and “nothing” produced no reaction.
All in all, the lab Effect of the Presence of a Catalyst was valid and quite successful. I believe there are a few things I would change. For instance, I would conduct more than one trail in order to have more accurate lab. After completing this experiment, I believe that there were no major problems indentified. If I were to conduct this experiment again I would like to test more catalysts and compare the results.