# Periodic Trend Game: Learning to predict elements using periodic trends

#### Summary

Students learn the meaning of Periodicity, how and why the periodic table is organized, and some of the trends in the periodic table. They do this by playing a game that is sort of a puzzle in which there is one piece missing and they need to figure out what it looks like and where it belongs.

## Learning Goals

This activity is designed for students to learn what periodic trends are and to reveal the importance of the periodic table's organization. This activity develops critical thinking skills, data analysis skills, observational skills, along with modeling a simple periodic table. It also introduces students to the concept of periodicity by forcing them to find trends and use them to predict what their "element" will look like. Vocabulary that can be introduced using this game are things like atomic mass, atomic number, periodicity, electronegativity, atomic radius, reactivity, ionization energy.

## Context for Use

This activity is designed to be used in a general chemistry class with 11th & 12th grade students as a introduction to a unit on the periodic table. This activity can be done with any class size as long as enough puzzles are available. I pair my students and give each pair one puzzle. I have tried groups of three but found pairs to work better. This activity can be done in a single class period. The number of trends your puzzles contains can easily manipulate the level of difficulty; it is easily adaptable.

## Description and Teaching Materials

In this game students are given a set of 24 hand made cards (with one card missing). The set of cards is made from colored construction paper, various stickers, and markers. There are 4 colors used making six cards of each color. Each card in the set has 2 numbers on it similar to atomic number and mass number. Along with the numbers three sets of stickers are used to represent various periodic trends. Students are given the deck of cards with one card missing and are given directions to determine the qualities of their missing card. They must determine its color, the numbers present on it, and the type and number of stickers on it. I offer very little advice on how to go about figuring this out other than lay them out and see what makes sense.

I use this activity with my general chemistry class as an introduction to the periodic table. For many this is a challenging activity at that level. I challenge the few that get it quickly to try to present a different way of laying out the cards in which trends are still able to predict their elements, offering them extra-credit for this. The game typically takes most classes working in pairs approximately 40 minutes to have everyone complete. It is important that finished students not reveal the "secret" to groups still working, removing different cards from each deck helps prevent this. Each deck of cards is somewhat unique to prevent them from comparing decks to determine the missing card.

Colors, numbers, and stickers are arranged differently. Students are allowed two guesses per grade on the activity (so 1-2 guesses "A" , 3-4 guesses "B", 5-6 "C", if they are able to correctly id their card then I do not give them anything lower than a "C"). As students are making their guesses I do not answer any questions with an answer other than yes that is the card or no that is not exactly what the card looks like. Once all groups have correctly identified their missing card I take ~15 minutes to discuss the significance of the trends and how the periodic table uses similar trends in element properties to organize the elements accordingly.

## Teaching Notes and Tips

The time required for this activity can be shortened by giving hints to students, such as looking for patterns, does that layout work for all sets of data?, etc.. It is important that you keep those who have figured it out from becoming too involved in other groups' puzzles or slower students will not truly figure it out and make the connection to Periodicity and being able to predict element properties. This activity is a different way to present material that offers students something concrete to apply periodic trends to, and thus a better way of seeing the periodic table as a tool rather than a chart of properties.

## Assessment

Since I use this activity as an introduction to the periodic table I do not formally assess students at this time. I also present this material in greater depth, directly looking at the periodic table and its trends such as ionization energy, atomic radius, reactivity, etc. This activity offers students a model or reference to compare the periodic table to while learning about it and its uses. I award points for completion of this activity according to the number of guesses students make to correctly identify their missing piece.

## Standards

9-12.II.A.2-Elements position in the table
9-12.II.A.3-Compare an elments properties
9-12.II.A.4-Id groups, periods, and families