Students watch a video that demonstrates the increasing reactivity of alkali metals then post possible reasons/explanations on padlet. You will need to create your own padlet page for students to access. The link is to the padlet home page.
2 Evidence Gathering
Students will use google sheets to create a data set for ionization energy. The data set should be used to generate various different charts for analysis. This process should illuminate the pattern of ionization energy on the periodic table. Any number of charts can be used. You may choose to have a discussion about which chart type was the most informative for this application.
This periodic table contains the data for the ionization energies of all the elements. Use google sheets to create a data table that includes the element name, atomic number, ionization energy, and family (you should have four columns). You must use atomic numbers 1-20.
Use the Insert Chart option to create a column chart of ionization energy. Is there a pattern to the columns? If so, what is it?
Use the Insert Chart option to create an area chart of ionization energy and family. Is there a pattern? If so, what is it?
Try creating a few more chart types on your own. Continue to look for and describe patterns that emerge in the charts.
3 Analysis of Data
Students need to know what ionization energy is to make sense of the data. Begin with a discussion of ionization energy (knowledge of ions would be beneficial prior to this lesson). You could keep it pretty basic, just compare the metals losing electrons to the nonmetals gaining electrons. Next, discuss why things react in relation to electron transfer. Have students return to their data and charts. Have them write questions related to the data/charts independently, then share with a partner, then share out to the class. Record the questions (projector, doc cam, white board, etc). Ask the students to vote on which two or three are the most important/relevant to figuring out why the alkali metals react the way that they do. This is a good time to revisit the video from the hook. Have the students work on answering the selected questions; they must cite evidence from their data in each response.
4 Publish Conclusion
Have the students return to the same padlet wall they posted to in the beginning of the lesson. They should take a minute to read their initial thoughts (hypothesis) and then add their conclusions to their original post. They should not delete their hypothesis. Instead, they should support or refute it with the evidence they have gathered and examined. As the posts are going up find a few to use as exemplars and share them with the class after all conclusions have been posted.
This could be done on paper as an exit ticket. On socrative, ask this question of the students: Of the following group of elements, which one would you expect to be the most reactive? Explain your reasoning. Elements: phosphorous, sulfur, chlorine, argon.
You chould choose to go with least reactive instead of most, change the elements in the group, etc.