The Mendeleev Lab of 1869 Chemistry I Fall

The Mendeleev Lab of 1869 Chemistry I Fall 2011

Purpose of this lab: • To identify unknown elements based on observed trends in properties. • To learn how to write the results, discussion, and conclusion sections of a lab report in order to learn from the lab.

Problem • You have to identify nine unknown elements. • The elements are from the following groups: 1, 2, 11, 13, 14, 17, 18 Nothing from row 7 ! You may not use your textbook or other reference materials.

Materials at each station • Blank Periodic Table • Known and Unknown Element Property Cards • Samples of known elements

Day One Procedure 1. Go through the known element cards – if you see the word observe, then look at the actual element sample and write down your observations on that card. 2. Arrange all known cards in an order that follows the actual periodic table. 3. Jot dot in your notebook what patterns might exist across a row; Do the same for patterns down a group.

Day Two Procedures 1. Talk to text: Results, discussion and conclusion section of “Parts of a Lab” 2. Example Graph What graphs can you design for showing periodic trends from your data? 3. With the write up in mind, complete your graphs (minimum of three). 4. Based on your graphs, fill out the following: Unknown # Predicted Element Reasoning

Lab Report • Results (What did you find? ) – Summary Statement(s) – Visuals with written summary of visuals or more detail about visual • Discussion (What does it mean? ) – Can you identify the unknown elements based on periodic trends? What is your evidence? – Compare your unknown predictions with other groups in the class. Are your unknown predictions consistent with the other groups? Why or why not? • Conclusion (What have I learned about periodic trends? )