About Periodic Trends


Highly Recommended
Like all our Science Reasoning Center activities, Periodic Trends provides information about a phenomenon, experiment, or data presentation to answer questions. This information is accessible by tapping on the small thumbnails found on the bottom right of every question. However, it may be considerably easier to have a printed copy of this information or to display the information in a separate browser window. You can access this information from this page





The Standards
The Periodic Trends is an NGSS-inspired task includes five parts. In the activities, students will identify trends in atomic size and metallic character (ease at which electrons are lost), use trends in electronegativity to predict the type of bond formed between a given element and three other elements in the table, and relate trends in outer shell electron arrangements to the formula of a molecular compound. The activity addresses the HS-PS1-1 Performance Expectation of the Next Generation Science Standards.

This NGSS-inspired task consists of five parts. Each part involves a different type of skill or understanding. Collectively, the five parts were designed to address the following NGSS performance expectation:


HS-PS1-1:
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.


As a whole, the questions in this task address a wide collection of disciplinary core idea (DCI), crosscutting concepts (CCC), and science and engineering practices (SEP). There are 71 multi-part questions organized into 20 Question Groups and spread across the five activities. Each question is either a 2D or (preferably) a 3D question. That is, the task of answering the question requires that the student utilize at least two of the three dimensions of the NGSS science standards - a DCI, a CCC, and/or an SEP.



The following DCI, SEPs, and CCCs are addressed at some point within Periodic Trends:

DCI:  PS1.A: Structure and Properties of Matter
  • Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.
  • The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states.


 
SEP 2.3:  Developing and Using Models
Develop, revise, and/or use a model based on evidence to illustrate and/or predict the relationships between systems or between components of a system.


SEP 2.4:  Developing and Using Models
Develop and/or use multiple types of models to provide mechanistic accounts and/or predict phenomena, and move flexibly between model types based on merits and limitations.


SEP 6.3:  Constructing Explanations and Designing Solutions
Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.



CCC 1.1: Patterns
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.


CCC 2.3: Cause and Effect
Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.


CCC 6.2: Structure and Function
The functions and properties of natural and designed objects and systems can be inferred from their overall structure, the way their components are shaped and used, and the molecular substructures of its various materials.

 

 


Here is our NGSS-based analysis of each individual activity of the Periodic Trends Science Reasoning task. The core ideas, crosscutting concepts, and science and engineering practices that we reference in our analysis are numbered for convenience. You can cross-reference the specific notations that we have used with the listings found on the following pages:  
Disclaimer: The standards are not our original work. We are simply including them here for convenience (and because we have referenced the by number). The standards are the property of the Next Generation Science Standards.
 

Part 1: Charge, Distance, and Periodic Trends

This activity consists of 16 forced-choice questions organized into four Question Groups. Students are presented with a period or a group of the periodic table. For that period or group, they must predict trends associated with charge, nucleus-outer electron shell distances, number of valence electrons, and attractive forces. A Periodic Table hilighting the location of all possible elements is also provided. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 


NGSS Claim Statement: 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.

 
Target DCI(s) Target SEP(s) Target CCC(s)
Structure and Properties of Matter
PS1.A
Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.
 

The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states.

Developing and Using Models
SEP 2.4

Develop and/or use multiple types of models to provide mechanistic accounts and/or predict phenomena, and move flexibly between model types based on merits and limitations.

Constructing Explanations and Designing Solutions
SEP 6.3
Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.
Patterns
CCC 1.1
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

Cause and Effect
CCC 2.3
Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.
 



 

Part 2: Atomic Radius Trends

This activity consists of 16 forced-choice questions organized into four Question Groups. Students are presented with three elements in either a period or a group. A Periodic Table hilighting their location is also provided. Students must identify the element with the greatest atomic radius. They must also give a reason for the claim, expressed in terms of charge interactions or principal energy level. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 

NGSS Claim StatementUse the periodic table as a model to predict the relative atomic radii of elements based on the patterns of electrons in the outermost energy level of atoms.

 
Target DCI(s) Target SEP(s) Target CCC(s)
Structure and Properties of Matter
PS1.A
Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.
 

The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states.


Constructing Explanations and Designing Solutions
SEP 6.3

Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena.

Developing and Using Models
SEP 2.3

Use a model based on evidence to predict the relationships between systems or between components of a system.

 

Cause and Effect
CCC 2.3

Cause and effect relationships can be predicted for complex natural systems by examining what is known about smaller scale mechanisms within the system.

Patterns
CCC 1.1
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.
 



 

Part 3: Metallic Character Trends

This activity consists of 12 forced-choice questions organized into four Question Groups. Students are presented with three elements; they could be part of different groups and periods. A Periodic Table hilighting their location is also provided. Students must identify the element that most easily loses electrons. They must also give a reason for the claim, expressed in terms of charge interactions or principal energy level. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 

NGSS Claim Statement: Use the periodic table as a model to predict the relative ease at which elements lose electrons based on the patterns of electrons in the outermost energy level of atoms.

 
Target DCI(s) Target SEP(s) Target CCC(s)
Structure and Properties of Matter
PS1.A
Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.
 

The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states.

.
Developing and Using Models
SEP 2.4

Develop and/or use multiple types of models to provide mechanistic accounts and/or predict phenomena, and move flexibly between model types based on merits and limitations.

Constructing Explanations and Designing Solutions
SEP 6.3
Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.

Cause and Effect
CCC 2.3

Cause and effect relationships can be predicted for complex natural systems by examining what is known about smaller scale mechanisms within the system.

Patterns
CCC 1.1
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.
 



 

Part 4: Electronegativity Trends and Bond Type

This activity consists of 11 forced-choice questions organized into four Question Groups. Students are presented with three elements and a table of electronegativity values. They must determine which of the three elements would form an ionic bond with a fourth element, which would form a decidedly polar, covalent bond with a fourth element, and which would form a covalent bond that is either non-polar or borders being non-polar. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 

NGSS Claim Statement: Use the periodic table as a model to predict the relative the type of bonds elements form with each other based on the patterns of electrons in the outermost energy level of atoms.

 
Target DCI(s) Target SEP(s) Target CCC(s)
Structure and Properties of Matter
PS1.A
Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.
 

The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states.

Developing and Using Models
SEP 2.3

Uuse a model based on evidence to predict the relationships between systems or between components of a system.

Constructing Explanations and Designing Solutions
SEP 6.3
Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.
Patterns
CCC 1.1
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

Structure and Function
CCC 6.2
The functions and properties of natural and designed objects and systems can be inferred from their overall structure, the way their components are shaped and used, and the molecular substructures of its various materials.
 




 

Part 5: Covalent Bonds, Formulae, and Periodic Trends

This activity consists of 16 forced-choice questions organized into four Question Groups. Students are presented with the formula of a molecular compound formed by a main group nonmetal and unknown element X. They are given the Lewis electron dot diagram of the nonmetal. Given the formula, they must identify the Lewis electron dot structure of element X and identify the Group number that element X is in. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 

NGSS Claim Statement: Use the periodic table as a model to predict the relative the number of covalent bonds a nonmetal forms with other nonmetals based on the outermost energy level of atoms.

 
Target DCI(s) Target SEP(s) Target CCC(s)
Structure and Properties of Matter
PS1.A
Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.
 

The periodic table orders elements horizontally by the number of protons in the atom’s nucleus and places those with similar chemical properties in columns. The repeating patterns of this table reflect patterns of outer electron states.

Developing and Using Models
SEP 2.3

Uuse a model based on evidence to predict the relationships between systems or between components of a system.

Constructing Explanations and Designing Solutions
SEP 6.3
Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.
​Patterns
CCC 1.1
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

Structure and Function
CCC 6.2
The functions and properties of natural and designed objects and systems can be inferred from their overall structure, the way their components are shaped and used, and the molecular substructures of its various materials.
 




 








Complementary and Similar Resources

The following resources at The Physics Classroom website complement the Periodic Trends Science Reasoning Activity. Teachers may find them useful for supporting students and/or as components of lesson plans and unit plans.

Concept Builders, Chemistry - Properties of Matter: Metals, Nonmetals, Metalloids

Concept Builders, Chemistry - Properties of Matter: Subatomic Particles

Concept Builders, Chemistry - Atomic and Molecular Models: Complete Electron Configuration

Concept Builders, Chemistry - Atomic and Molecular Models: Periodic Table Battleship

Concept Builders, Chemistry - Atomic and Molecular Models: Periodic Trends

Concept Builders, Chemistry - Atomic and Molecular Models: Ionic Bonding