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Trend Setter Lab

Deanna Cullen's picture
Wed, 10/10/2012 - 11:57 -- Deanna Cullen
Trendsetter Lab

Students will proceed through a pre-lab engagement activity, organize element cards based on similarities & trends, discuss trends with the class and then produce a periodic table that includes the trends discussed within the lab. The teacher will check for student understanding at specific points as groups work together.

Concepts: 
  • The student will be able to identify trends of electronegativity, atomic radii and ionization energy on the periodic table.
  • The student will be able to explain the periodicity of the trends of electronegativity, ionization energy and atomic radii found on the periodic table.
  • The student will be able to identify elements with similar properties based upon their location on the periodic table. 
  • The student will be able to predict properties of elements based upon where that element is found on the periodic table.
Time required: 

Two 60 minute class periods for procedure. You may wish to include more time for discussion. The assessment portion can be done as homework.

Materials: 

Goggles                                                           Element card set

0.50 gram magnesium ribbon                          Periodic table outline

2-100 mL beakers                                           Distilled water

2-250 mL beakers

Phenolphthalein indicator solution

Procedure: 

Fig. 1.  Outline of Main Group Elements 

 

 

 

 

 

 

 

 

  

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1.  Obtain a set of element cards.  The cards represent the actual main group elements, but the element symbols have been replaced with a random code.  Less than half of the cards show the atomic mass of the element represented on the card.

 2.  Obtain cards Gg, Jj, Pp, Rr, Ss, Tt, Vv, Ww, Yy, Zz.  Place them in order of increasing atomic mass, using Fig. 1 as a reference.

 __________  Check Point -- Have your teacher check your table before you move on.

3.  Using the information on each of the remaining cards, continue to build the table by arranging the cards into eight groups and four periods (see fig. 1).  Also place the UNKNOWN ELEMENT where you think it belongs. 

 4.  a)  Record the properties you used to arrange the cards.  Explain how they helped in your arrangement of the cards.

 __________  Check Point -- Have your teacher check your table before you move on.

5.  Look at the table you created.  List other patterns and/or trends you used while arranging the element cards that you did not already list in #4.  (You should discuss at least five properties between questions #4 & #5.)

 6.  Identify where the metals, metalloids and nonmetals are found on the table.

 7.  Identify where most of the gases are found on the table.

 __________  Check Point -- Have your teacher check your work before you move on.

 PROCEDURE -- Part B

 1.  Place about 100 ml of distilled water in each of two 250 mL beakers.

2.  Add one drop of phenolphthalein to the water in each beaker.  Phenolphthalein turns hot pink in a basic solution (pH 7-14). 

3.  Add about 0.50 grams of calcium turnings to one beaker. 

4.  Add about 0.50 grams of magnesium to the other beaker. 

5.  Record your observations.

 CALCIUM                                                     MAGNESIUM

 

Answer the following questions.

1.  The elements calcium and magnesium belong in group 2 under card Jj on the table of cards you developed.  Given your observations, predict which element belongs directly under Jj and describe your reasoning.

 2.  a)  Is there a trend of reactivity in group 2?  If yes, what is it. 

 b)  Look at other groups on your table.  Do you see a consistent trend of reactivity within groups and periods on your table?  Describe what you see.

 __________  Check Point -- Have your teacher check your work before moving on.

 PROCEDURE -- Part C

 There were several blanks on Mendeleev’s original table.  He not only predicted that these elements were yet to be discovered, but he also predicted the properties of these missing elements based upon the trends he found within his table.  When these elements were discovered, their properties were very close to Mendeleev’s predictions. 

 Look at the UNKNOWN ELEMENT card in your table.  Use the trends within the table to make the following predictions.

 1.  Predict what phase this element will be in at room temperature and explain your reasoning.

 2.  Predict what the appearance of this element will be and explain your reasoning.

 3.  Predict the ratio that this element will combine with oxygen and explain your reasoning.

 4.  Predict the ratio between this element and fluorine when they combine and explain your reasoning.

 __________  Check Point -- Have your teacher check your work before moving on.

  See a more detailed version of the procedure in the attached Student Version.        

   

 

 

Questions: 

See the Student Version of the Trend Setter Lab for Discussion questions and Assessment options.

Preparation: 

10 minutes to prepare magnesium, calcium and lab supplies for Part B.

Attribution: 

I developed this inquiry activity as part of a program called Target Inquiry at Grand Valley State University in Michigan between 2008 and 2010. I encourage you to check out the other activities that are posted on the Target Inquiry Web site along with the Teacher Guide that supports this activity. Thanks to the Target Inquiry Team for allowing JCE ChemEdX to post my activities here. The Target Inquiry site is free, however they do request that you register yourself as a user to allow them to track the usage of the activities.

Teacher Document: 
Chemistry Domain: 
Chemistry Topic: 

Comments

Sarah Kong's picture
Submitted by Sarah Kong on

This lab is fabulous!  My students were frustrated at just the appropriate level!  They were interested, able to work through their difficulty, and continued to refer back to this lab throughout our discussions on periodic trends.  Thanks, Deanna!

~ Sarah Kong

Chemistry Teacher