Do this before you come to lab (have at the top of your notebook page to begin the lab):

1. Safety: What are the potential hazards and safety considerations when working with concentrated chemical reagents compared to working with diluted chemical reagents?
2. Purpose: Write a few sentences about the purpose of this lab: What is the “big picture” viewpoint of the lab experiment? What question am I trying to answer? What data will be collected to answer the questions? What technique will I use to obtain these data?
3. Preparation: Answer the following questions:
   1. Is ethanol a strong base?
   2. Is ethanol a strong nucleophile? Explain your reasoning.
   3. How will the pH change when you mix the alkyl halide with ethanol? Which available indicator will allow you to observe this change?

Your Laboratory Challenge:

General reaction procedure (2 people per group):

To the 2 mL tube, first add 1 mL of ethanol followed by 1 drop of the indicator solution. Once several solutions are ready, added 4 drops of the alkyl halide to the tube. Lightly screw the top on the tube (do NOT tighten) and place at the desired temperature checking every 2 mins for color change, no longer than 16 mins.

Goal of the experiment:

Your goal during this experiment is to find the experimental conditions that produce the fastest reaction and to obtain enough data to justify your claims in your lab report. Your experimental options are laid out below:

Indicators available: phenolphthalein and methyl red

Temperatures available: room temperature, 40 °C, 60 °C (don’t go higher)

Alkyl halides available: 1-chlorobutane (1°), 2-chlorobutane (2°), tert-butyl chloride (3°, also known as 2-chloro-2-methylpropane),

Using the above procedure and the available options, first make a plan to systematically answer the question, followed by the execution of the plan. Remember to use controls in your experimental design.

Communicating Your Results

For a permanent record, both your data and report should be written in your notebook.

1. Safety
2. Purpose
3. Preparation
4. Which set of conditions do you hypothesize will result in the fastest reaction? Which indicator do you hypothesize will work best for this reaction? Provide a brief explanation for both.
5. Devise a plan to thoroughly test these predictions.
6. Make a table (or tables) of your results.
7. What conclusions can you draw from your data? Was your prediction correct?
8. Explain why the conditions that resulted in the fastest reaction led to this reaction being the fastest. Make sure to include an energy diagram in your explanation.
9. How could the rate of this reaction be measured more quantitatively?
10. Make a prediction about how the conditions could be modified to increase the rate of the reaction?
11. Write a brief conclusion paragraph: comment on whether or not you achieved the goal of the experiment, respond to the questions posed in the introduction.  Support your conclusion using your data.