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.
- 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.
Two 60 minute class periods for procedure. You may wish to include more time for discussion. The assessment portion can be done as homework.
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
Fig. 1. Outline of Main Group Elements
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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.
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.
See the Student Version of the Trend Setter Lab for Discussion questions and Assessment options. Log into your ChemEd X account to view this document in the Supporting Information.
10 minutes to prepare magnesium, calcium and lab supplies for Part B.
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 Student and Teacher Guides that supports this activity. Thanks to the Target Inquiry Team for allowing 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.
Safety
General Safety
General Safety
For Laboratory Work: Please refer to the ACS Guidelines for Chemical Laboratory Safety in Secondary Schools (2016).
For Demonstrations: Please refer to the ACS Division of Chemical Education Safety Guidelines for Chemical Demonstrations.
Other Safety resources
RAMP: Recognize hazards; Assess the risks of hazards; Minimize the risks of hazards; Prepare for emergencies
NGSS
Matter and its Interactions help students formulate an answer to the question, “How can one explain the structure, properties, and interactions of matter?” The PS1 Disciplinary Core Idea from the NRC Framework is broken down into three subideas: the structure and properties of matter, chemical reactions, and nuclear processes. Students are expected to develop understanding of the substructure of atoms and to provide more mechanistic explanations of the properties of substances. Chemical reactions, including rates of reactions and energy changes, can be understood by students at this level in terms of the collisions of molecules and the rearrangements of atoms. Students are able to use the periodic table as a tool to explain and predict the properties of elements. Using this expanded knowledge of chemical reactions, students are able to explain important biological and geophysical phenomena. Phenomena involving nuclei are also important to understand, as they explain the formation and abundance of the elements, radioactivity, the release of energy from the sun and other stars, and the generation of nuclear power. Students are also able to apply an understanding of the process of optimization in engineering design to chemical reaction systems. The crosscutting concepts of patterns, energy and matter, and stability and change are called out as organizing concepts for these disciplinary core ideas. In the PS1 performance expectations, students are expected to demonstrate proficiency in developing and using models, planning and conducting investigations, using mathematical thinking, and constructing explanations and designing solutions; and to use these practices to demonstrate understanding of the core ideas.
*More information about this category of NGSS can be found at https://www.nextgenscience.org/dci-arrangement/hs-ps1-matter-and-its-interactions.
"Matter and its Interactions help students formulate an answer to the question, “How can one explain the structure, properties, and interactions of matter?” The PS1 Disciplinary Core Idea from the NRC Framework is broken down into three subideas: the structure and properties of matter, chemical reactions, and nuclear processes. Students are expected to develop understanding of the substructure of atoms and to provide more mechanistic explanations of the properties of substances. Chemical reactions, including rates of reactions and energy changes, can be understood by students at this level in terms of the collisions of molecules and the rearrangements of atoms. Students are able to use the periodic table as a tool to explain and predict the properties of elements. Using this expanded knowledge of chemical reactions, students are able to explain important biological and geophysical phenomena. Phenomena involving nuclei are also important to understand, as they explain the formation and abundance of the elements, radioactivity, the release of energy from the sun and other stars, and the generation of nuclear power. Students are also able to apply an understanding of the process of optimization in engineering design to chemical reaction systems. The crosscutting concepts of patterns, energy and matter, and stability and change are called out as organizing concepts for these disciplinary core ideas. In the PS1 performance expectations, students are expected to demonstrate proficiency in developing and using models, planning and conducting investigations, using mathematical thinking, and constructing explanations and designing solutions; and to use these practices to demonstrate understanding of the core ideas."
Students who demonstrate understanding can use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
*More information about all DCI for HS-PS1 can be found at https://www.nextgenscience.org/dci-arrangement/hs-ps1-matter-and-its-interactions and further resources at https://www.nextgenscience.org.
Students who demonstrate understanding can use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.
Assessment is limited to main group elements. Assessment does not include quantitative understanding of ionization energy beyond relative trends.
Examples of properties that could be predicted from patterns could include reactivity of metals, types of bonds formed, numbers of bonds formed, and reactions with oxygen.
Students who demonstrate understanding can construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.
*More information about all DCI for HS-PS1 can be found at https://www.nextgenscience.org/dci-arrangement/hs-ps1-matter-and-its-interactions and further resources at https://www.nextgenscience.org.
Students who demonstrate understanding can construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.
Assessment is limited to chemical reactions involving main group elements and combustion reactions.
Examples of chemical reactions could include the reaction of sodium and chlorine, of carbon and oxygen, or of carbon and hydrogen.
All comments must abide by the ChemEd X Comment Policy, are subject to review, and may be edited. Please allow one business day for your comment to be posted, if it is accepted.
Comments 1
Trend Setter
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!