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Online Lab Submission

Students:

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Virtual Labs:

Pre-Lab Assignments

Interactive Animations:

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Ordering Procedure Steps

This interactive pre-lab activity requires students to arrange lab procedure steps in the correct order. To complete it successfully, students must consult the procedure in their lab guide.

Each student receives a randomized subset of steps (e.g., 15 out of 20) to discourage identical answers. In the example shown, 17 total steps exist, but only 13 are displayed; refreshing the page generates a new selection and order.

In the example below, the lab has 17 procedure steps (listed) but the ordering animation only displays 13 steps.



  1. Record your unknown number.
  2. Mass a clean, dry Pyrex test tube.
  3. Add 2.5 - 3.0 g Unknown to the test tube.
  4. Take the unknown to the Hood.
  5. Heat the unknown to decompose the ammonium bicarbonate.
  6. Determine the mass of ammonium bicarbonate in the mixture.
  7. Add ~ 5 mL water to the test tube.
  8. Heat the test tube with a Bunsen burner for ~ 60 seconds.
  9. Add a 2nd 5 mL of water to the test tube and heat gently for 60 seconds.
  10. Add a 3rd 5 mL of water to the test tube and heat gently for 60 seconds.
  11. Use a Bunsen burner to dry the wet sand.
  12. Determine the mass of sand in the mixture.
  13. Heat the salt water solution in the Evaporating Dish.
  14. Determine the mass of the salt in the unknown mixture.
  15. Discard the salt and sand in the trash container.
  16. Clean the used glassware with soap and water.
  17. Return the ironware to the appropriate location.


Students complete the activity by:

  • Reviewing the lab procedure
  • Dragging and ordering the steps
  • Submitting their answers
  • Revising any incorrect steps (highlighted in red) until all are correct (green)

This tool is used as both a pre-lab and in-lab assessment to evaluate understanding before the experiment. It is active - adjust the order and click Submit to check your answer.

The same format can also be applied to other topics, such as ordering electromagnetic radiation (by energy or wavelength) or ranking atoms and ions by periodic trends (e.g., atomic radius, electronegativity, ionization energy, electron affinity).