Lab Skills Videos

The lab notebook

Additional information

Key Takeaways

  • The lab notebook is where you should include all information related to a procedure, including any deviations from the procedure, data collected, mathematical calculations, and reflection of the experiment.
  • Look at the rubric for how lab notebook pages are assessed if you are unsure if you included something.

Submitting lab reports

Additional information

Key Takeaways

  • Most documents are submitted online through the DropBox in Canvas as PDFs.
  • There are many ways to generate PDFs of your lab pages; finding the best method for YOU is what is important.

Excel basics

Additional information

Key Takeaways

  • Using Excel will be a critical skill for success in analytical chemistry. Practice if needed!

Visualizing data

Additional information

Key Takeaways

  • Choosing a graph that best fits your goals when you display your data is important. Many programs can make graphs, although we provide guidance in Excel.
  • Common graphs we will make in this class include making calibration curves (using a scatter plot).

Using a balance

Additional information

Key Takeaways

  • Keeping the balance clean and caring for it appropriately will impact the accuracy of your measurements.
  • Different balances have different errors; make sure you are using the correct balance.
  • (1) Weighing by addition and (2) weighing by subtraction have different applications; pay attention to which is best for your experiment!

Observations while using a balance

Additional information

Key Takeaways

  • Careful preparation before you take a measurement will change the accuracy of your weight.
  • Take care to make sure your balance has a stable measurement prior to writing down the weight of the material.

Preparing and caring for dried samples

Additional information

  • N/A

Key Takeaways

  • Some samples need to be dried (i.e., removal of water) before used, as water can influence the accuracy of the weight of the analyte your measure out.
  • Pick the correct oven temperature to dry your sample.
  • Prepare your desiccator to be able to store your dry samples throughout the semester.

Glassware overview

Additional information

  • Reference your specific glassware for their tolerances.

Key Takeaways

  • There are 2 major types of glassware: volumetric and non-volumetric.

Cleaning glassware

Additional information

  • N/A

Key Takeaways

  • Glassware cleanliness can impact the accuracy of your analysis.
  • Non-volumetric glassware can be washed with soap, but volumetric glassware should be washed with a special microcleaner.

Using volumetric flasks

Additional information

  • Reference your specific glassware for their tolerances.

Key Takeaways

  • Each flask as a specific tolerance and class that would be useful to note and write in your lab notebook.
  • Volumetric flasks are TO CONTAIN pieces of glassware, meaning the are calibrated TO CONTAIN a specific volume.
  • Form a slurry prior to adding solid into your volumetric flask.
  • Make sure you are mixing often!
  • Pour your solution into a different container before using the solution for other purposes.

Using volumetric pipettes

Additional information

  • Reference your specific glassware for their tolerances.

Key Takeaways

  • Each pipette as a specific tolerance and class that would be useful to note and write in your lab notebook.
  • Volumetric pipets are TO DELIVER pieces of glassware, meaning the are calibrated TO DELIVER a specific volume.

Using a buret

Additional information

  • Reference your specific glassware for their tolerances.

Key Takeaways

  • Burets have a specific tolerance and class that would be useful to note and write in your lab notebook.
  • Burets are a TO DELIVER piece of glassware, meaning the are calibrated TO DELIVER a specific volume.
  • Carefully prepare the buret, including rinsing it well and removing any bubbles, before making any measurements.
  • Make sure you are making all measurements at eye level.

Titrations

Additional information

  • N/A

Key Takeaways

  • Titrations are a classic analytical technique to determine the concentration of an unknown sample.

Filtering samples

Additional information

  • N/A

Key Takeaways

  • There are 2 different ways to filter samples: gravity filtration and vacuum filtration.

Transferring Small Volumes

Additional information

  • N/A

Key Takeaways

  • We have many tools to transfer small volumes, including multiple types of pipettes. Make sure you choose a tool that has your required accuracy, precision, and flexibility (as needed).

Using a spectrophotometer

Additional information

Key Takeaways

  • Spectrophotometers (connected to a LabQuest) can allow us to measure how much light a molecule absorbs (or emits)!
  • Proper preparation of the cuvet and acquisition settings are important!

Using a pH probe

Additional information

Key Takeaways

  • Make sure you are using a 2-point calibration (pH=7 and 10 or 7 and 4), and it is recommended to calibrate everyday (or even multiple times a day)!
  • Before using the pH probe, make sure it was properly stored and is intact before using it.

Performing an automated titration

Additional information

  • N/A

Key Takeaways

  • Assemble the apparatus with care and consideration for the orientation.
  • Make sure you calibrate all the necessary pieces, including the probe you use (redox or pH) and the drop counter.

Transferring data from the LabQuest

Additional information

  • N/A

Key Takeaways

  • Make sure you have an appropriately sized flashdrive to transfer your data off the LabQuest.
  • Different analyses will have different formats when exported from the LabQuest; with proper notes in your lab notebook, you should be able to arrange the data!

Using an HPLC

Additional information

Key Takeaways

  • Each HPLC will have a mobile phase, a pump, a way to add sample to the system, a column, and a detector, all of which should be customized to the analytes you are analyzing.
  • The instrument already has a loop that measures an exact volume of sample that is to be injected; just make sure you put in excess! Make sure you load in the “Load” position.
  • See the software instructions on how to analyze your data.

Gas chromatography

Additional information

Key Takeaways

  • Gas chromatography is a separation technique that analyzes samples that can be gaseous.
  • Data from a GC can be both qualitative (retention time) and quantitative (peak area or peak height).
  • Knowing how to use the instrument will be key to your success in the lab!
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UW Madison Manual of Experiments for Analytical Chemistry Copyright © by Chem 327/329 Team. All Rights Reserved.