Lab 6-2B: Factors Affecting Reaction Rates Lab Report

Name: Brandon Jansen

Date: Mar. 6, 2013

Block: D

How to Write a Science Lab Report

Use the following headings in order, for each lab write up. (Each heading should always be underlined with a ruler)

Title: Write down the name of the experiment or activity of the lab

Lab 6-2B: Factors Affecting Reaction Rates                                                        (/2)

Purpose: Summarize in 1-2 sentences what you hope to explore or find out in this lab, based on the pre-lab material provided.         

What we hope to explore in this lab is to find if and what happens to the rate of a chemical reaction if it is affected by temperature, surface area and presence of a catalyst.                                   (/2)

Materials: List the equipment and chemicals/specimens you will be using to conduct the experiment. Always note any differences from the equipment you actually use and what is written in your text.

What we need for the lab is:

Part 1

·      Two 400 mL beakers

·      Ice water

·      Hot water

·      Thermometer

·      3 effervescent tablets

·      stopwatch

Part 2

·      3 small test tubes

·      Test tube rack

·      Dish soap

·      6% hydrogen peroxide solution (H₂O₂)

·      Potassium iodide (KI)

·      Copper (II) chloride (CuCl₂)

·      Sodium chloride (NaCl)

Part 3

·      Mortar and pestle

·      Sodium carbonate

·      4 small test tubes

·      Test tube rack

·      Dilute hydrochloric acid solution (HCl)

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Procedure:

Include a brief outline of the steps to follow. If you are using the textbook you can simply record “Refer to text, page __”

Part 1 Effect of Temperature

1.    Fill one beaker with ice water. Fill the second beaker with very hot water. Use a thermometer to measure the temperature in each beaker. Record the temperatures.

2.    Drop an effervescent tablet into each beaker at the same time. Observe. Use a stopwatch to measure how many seconds it takes for each tablet to finish dissolving. Record the times. Dispose of beaker contents down the sink.

                                                                                      

3.    Fill one of the beakers with a mixture of hot water and ice water. Adjust the temperature by adding more warm or cool water until the temperature is halfway between the temperatures recorded in step 1.

4.    Make a prediction of the length of time it will take for an effervescent tablet to finish dissolving. Record your prediction.

5.    Add a tablet to the water that is at a middle temperature. Observe and record the time it takes to dissolve. Dispose of beaker contents down the sink.

Part 2 Effect of Adding a Catalyst

1.Label three test tubes: KI, CuCl₂, NaCl. Place the test 
tubes in the test tube rack. Place one drop of dish soap into each test tube.

2.Into each test tube, pour 6% hydrogen peroxide to a depth of about 2 cm.

3.Add a pea-sized amount of solid KI, CuCl₂, and NaCl to the appropriate test tube. Observe. Record your observations, including which reaction rate is the fastest and which is the slowest.

4.Dispose of test tube contents as your teacher directs.

Part 3 Effect of Surface Area

6.Use the pestle to grind some sodium carbonate lumps into a fine powder in the mortar. Place the four test tubes in the test tube rack.

7.Place lumps of sodium carbonate into one of the test tubes to a depth of about 1 cm. Place some finely ground sodium carbonate into a second test tube to a depth of about 1 cm.

8.Measure dilute hydrochloric acid solution into the two remaining test tubes to a depth of about 2 cm.

9.Simultaneously, pour the dilute HCl solution into each of the test tubes containing sodium carbonate. Observe. Note which reaction was faster.

10.         Clean up and put away the equipment you have used. Follow your teacher’s instructions for disposal of wastes.

 “Refer to text, page 278-279”                                                                                              

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Results: This is the section where you will record your data that you collect and observations from carrying out the experiment. This may be in the form of:

                                                            

·      a diagram


·      a short list of observations


·      a table of results


·      a graph etc

Temperature:

Substances	Temperature	Time Effervescent Tablet Dissolved
Ice Cold Water	4oC	35 minutes at 10% left.
Very Hot Water	66oC	8:20 minutes

Presence of a catalyst:

Chemical	Fastest Reaction	What Happened With the Solution Mixed
KI	Fastest	Foam poured out of tube and was yellow.
CuCl2	Second Fastest	Foam formed a little bit and was light blue.
NaCl	Did not react	Was pink

Surface Area:

Solution	Fastest Reaction	What Happened With the Solution Mixed
Lumpy Sodium Carbonate	Second Fastest	Powder is not so hard, sticky and does not dissolve.
Grounded up Sodium Carbonate	Fastest	Powder is hard, sticky and does not dissolve.

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Discussion:

You will often be asked to answer some questions about your experiment. Your answers should be written in full sentences under this heading.

Analyze:

1. What is the relationship between rate of reaction and change in temperature?

The relationship between the rate of reaction and change in temperature is they both have either a liquid or a chemical changing at a certain speed. They both have some sort of reaction occurring that is making the state change and therefore changing state or temperature at a certain speed.

2. Compare your prediction in step 4 of the length of time it would take an effervescent table to dissolve at the middle temperature with how long it actually took.

At room temperature it probably would of dissolve at about 20 minutes.

3. (a) Which of the solutions that were added to the hydrogen peroxide solution may have acted as a catalyst?

The Copper II Chloride may have acted as a catalyst, because it made the reaction go fast and was not all used up.

(b) Which catalyst sped up there action the most?

The potassium iodide sped up their action the most.

4. Which has more surface area, a 5 g lump of sodium carbonate or 5 g of sodium carbonate powder?

The 5 g of sodium carbonate powder has more surface area.

5. How did surface area affect the rate of sodium carbonate decomposition in step 14?

It effected so the sodium carbonate did not mix into the solution and the powder got hard and sticky with the dilute HCl more so than the lumpy sodium carbonate.

Conclude and Apply:

1. Suppose a reaction involved a finely ground powder reacting with a concentrated acid. Suggest three methods of decreasing the reaction rate.

Three methods are:

·      To add only a little bit of powder to the concentrated acid.

·      Add more concentrated acid.

·      Mix the powder with two drops of a solid.

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Conclusion: Write a brief summary of your results and 2-5 sentences summarizing the key ideas learned from the experiment. The conclusion should link back to the original purpose. You should include possible sources of error and/or ideas to improve or expand your experiment next time.

Are results went well and successful since we followed the procedure. I learned from this experiment that the rate of a chemical reaction can be affected by temperature, presence of a catalyst and surface area. We had no errors, but we had a spill of the Potassium iodide with the hydrogen peroxide solution so next time we can be more careful and see what is going to happen so we have enough time to bring it to the sink and have it flow over in the sink not the test tube rack. Overall everything went successful and the experiment was really cool.

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