Consider before watching the videos:

What glassware would you use to transfer small amounts of liquid between containers? Why?

Lab Experiments (Write protocols based on the videos then complete your protocols as you perform experiments in class):

1. Charging the burette Note: our burette will be filled with 0.1M HCl
2. Titrating sodium hydroxide with HCl with phenolphthalein indicator
3. Titrating sodium hydroxide with HCl with methyl red indicator

 

Data analysis and calculations (Use these if you need help with your data and calculations)

1. pH
2. Titration of sodium hydroxide with hydrochloric acid

The prelab is due before your lab class meets and must include Experimental Protocol, Chemical Table and Equipment Table.

(Analysis) Watch the experiment videos. Take notes on the protocols. Stop the videos and re-watch as necessary to acquire details of the procedure. Write out the protocol for each part of the experiment.  (It can be written in sequential steps.  Complete sentences are not necessary.)  This is the protocol you follow, so be detailed.

(Analysis) Identify the equipment (type AND size) needed for the experiment and include the name and an image (picture) of each.  Be sure to describe the equipment, how to use it, and why it is suitable for this use.

Equipment Name	Equipment Picture or Description	Intended Purpose

(Acquiring competencies) Following your detailed protocol, perform all the experiments. Record your observations and take pictures of your key steps in the process. Your observations and images need to be incorporated in your data section and this section should be as detailed as possible as you will use this information to complete your data processing.  

Trial #	Concentration HCl (M)	Volume NaOH (mL)	Starting volume HCl (mL)	Ending volume HCl (mL)	Drops of phenolphthalein added (drops)	Color at start	Color at endpoint

   

Trial #	Concentration HCl (M)	Volume NaOH (mL)	Starting HCl volume (mL)	Ending volume HCl (mL)	Drops of methyl red added (drops)	Color at start	Color at endpoint

 

1. (Lab skills) Describe the steps to charge a burette.
2. (Representation) Write the balanced chemical equation that describes the chemical reaction between NaOH and HCl.
3. (Representation) Write the complete ionic equation that describes the chemical reaction between NaOH and HCl.
4. (Representation) Write the net equation that describes the chemical reaction between NaOH and HCl.
5. (Interpretation) Using your balanced chemical equation that describes the observed reaction, interpret its meaning on the microscopic and macroscopic scale.
6. (Existing knowledge, research, and views) Define the endpoint of a titration.
7. (Analysis) Provide a supported argument for the use of an indicator in your titration.
8. (Manipulation) Calculate the volume of HCl solution consumed in your last titration with phenolphthalein indicator. Consider units and significant figures.
9. (Manipulation) Calculate the moles of HCl consumed in your last titration with phenolphthalein indicator. Consider units and significant figures.
10. (Manipulation) Calculate the volume of NaOH solution neutralized in your last titration with phenolphthalein indicator. Consider units and significant figures.
11. (Manipulation) Calculate the concentration of your NaOH solution using your data from the pH titration.
12. (Analysis) Identify at least one of the 12 principles of green chemistry applied in this experiment. Justify your selection. 12 Principles of Green Chemistry
13. (Representation) Fill in the values in the table below for the experiment with phenolphthalein indicator with your calculated values.

 

Molarity HCl (M)	Starting volume HCl (mL)	Ending volume HCl (mL)	Volume added to color change (mL)	Volume added to color change (L)	Moles HCl at endpoint (mol)	Moles NaOH at endpoint (mol)	Volume NaOH   (L)	Molarity NaOH solution (mol/L)

 

14. (Manipulation) Calculate the volume of HCl consumed in your last titration with methyl red indicator. Consider units and significant figures.
15. (Manipulation) Calculate the moles of HCl consumed in your last titration with methyl red indicator. Consider units and significant figures.
16. (Manipulation) Calculate the volume of NaOH neutralized in your last titration with methyl red indicator. Consider units and significant figures.
17. (Manipulation) Calculate the concentration of your NaOH solution using your data from the pH titration.
18. (Representation) Fill in the values in the table below for the experiment with methyl red indicator with your calculated values.

 

Molarity HCl (M)	Starting volume HCl (mL)	Ending volume HCl (mL)	Volume added to color change (mL)	Volume added to color change (L)	Moles HCl at endpoint (mol)	Moles NaOH at endpoint (mol)	Volume NaOH   (L)	Molarity NaOH solution (mol/L)

 

19. (Analysis) Comment on the precision of your titrations with the phenolphthalein indicator and use your data to support your assessment.
20. (Analysis) Comment on the precision of your titrations with the methyl red indicator and use your data to support your assessment.
21. (Analysis) Compare the average NaOH concentrations from your phenolphthalein and methyl red titrations and make a supported argument for the indicator that is most suitable for this titration.
22. (Analysis) Provide a rationale for why there would be bubbles in the burette above the stopcock and how they would impact your titration if not removed.
23. (Lab skills) Describe what you would do to remove the bubbles above the stopcock of your burette.
24. (Analysis) Provide a rationale for why there would be bubbles in the burette below the stopcock and how they would impact your titration if not removed.
25. (Lab skills) Describe what you would do to remove the bubbles below the stopcock of your burette.
26. (Analysis) Provide a rationale for why there would be leakage around the stopcock and how this would impact your titration if not remedied.
27. (Lab skills) Describe what you would do to remedy the leakage around the stopcock of your burette.
28. (Analysis) Identify at least one of the 12 principles of green chemistry applied in this experiment. Justify your selection. 12 Principles of Green Chemistry
29. (Assumptions and analysis)

Assumptions made	Testing the assumption	If assumptions are wrong ...
Every drop from the burette is identical	Find the mass of 10 individual drops, and compare
The presence of phenolphthalein does not affect the titration result

 

Summary

The summary has two parts: an abstract and an experimental protocol reflecting the experiment that you actually performed. The abstract and experimental protocol should both be between 100-250 words, size 12 Arial font each. There may be multiple experimental protocols for one experiment.

Part 1.

Title of Experiment: Performed tasks and applied techniques to accomplish the goal of the experiment and a description of the system under study (the title you are given for the lab is insufficient). Ex. Calibration of burette techniques to determine endpoints in an acid – base neutralization reaction using phenolphthalein, sodium hydroxide and hydrochloric acid.

(This is a highlight of what you learned from performing the experiment and processing your collected data. Below is a template and an example of what you are expected to write.) In this lab experiment we investigated [purpose of your experiment] using [list the materials you worked with] and we found that [present the highlights of your results (include numbers)]. The results [present significant results]. The collected data compares to [draw conclusion about your results compared to other sources (this could be another group or the literature value)]. The [add type of measurement individually] measurement was collected using [describe instrument by sensitivity].   Think through this before writing:

1. Purpose: What were you trying to do?
2. Materials used: What chemicals and materials did you work with?
3. Method: What instruments were used to collect measurements and how were the measurements collected?
4. Results: What did you find out about the objects under study?
5. Significance: What did you learn about the precision and accuracy of your techniques? How do your determined values compare to reported values?

  Ex. In this quantitative lab, we investigated the neutralization of a …M NaOH solution with 0.1M HCl using a … indicator to identify the endpoint. The average NaOH concentration from the titration with  (indicator) was determined to be … (value units) and from the (indicator) it was determined to be …(value units). The result from the titrations with the two indicators were ( compare the results), because …..(describe the equipment used for the various measurements and their associated sensitivities).

Part 2.

Title of Protocol (Brief description of the experiment in bold) Ex. Setting up the Burette Ex. Making the Sodium Hydroxide Solution Ex. Titrating 0.15M NaOH with 0.1M HCl    

Experimental Protocol

(This is a condensed and organized description of the protocol you actually completed during class. Use the exact amounts of materials and list the exact equipment that you used in performing the experiment. The length of this section depends on the complexity of your experiment, usually 3-4 sentences maximum in one paragraph.)   (For each material and procedure)