Publication No. 14129
Super Value Laboratory Kit
Materials Included In Kit
Sets of element cards, 15
Additional Materials Required
This laboratory activity is considered nonhazardous. Remind students to exercise caution when working with scissors.
Cards may be stored for future use.
Correlation to Next Generation Science Standards (NGSS)†
Science & Engineering PracticesAsking questions and defining problems
Developing and using models
Analyzing and interpreting data
Constructing explanations and designing solutions
Obtaining, evaluation, and communicating information
Disciplinary Core IdeasMS-PS1.A: Structure and Properties of Matter
HS-PS1.A: Structure and Properties of Matter
Systems and system models
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.
Answers to Prelab Questions
Students should arrange their cards in the following order. Realize that GBA or GAB are both logical arrangements for period three.
Answers to Questions
Special thanks to Dr. Tim Schaap, Retired, Elk Grove High School, Elk Grove, IL, for sharing this activity with—providing the idea and the instructions for this activity to Flinn Scientific.
Have you ever gone to the video store and looked for a specific movie? The videos are arranged, or classified, according to type as well as alphabetically. This arrangement is an example of two-dimensional classification. All the videos in a particular section have something in common and arranged A to Z. When you come to a different section, the alphabetical arrangement is repeated. Experience for yourself how a method of two-dimensional classification led to the modern-day arrangement of the elements known as the periodic table.
In the years 1868–1870, Dmitri Mendeleev (1834–1907), a professor of chemistry at the University of St. Petersburg in Russia, was writing a new textbook called Principles of Chemistry. More than 60 individual elements were known, along with a great many facts about their properties. Mendeleev knew the atomic masses of the elements, their densities, boiling points, and melting points. What was missing was a way to organize these facts, a way to understand how individual facts related to each other—in short, a way to classify the elements. The following quote from Mendeleev reveals his thoughts at the time:
“I wished to establish some sort of system of elements in which their distribution is not guided by chance... but by some sort of definite and exact principle.”Mendeleev decided to arrange the elements according to atomic mass. He wrote out the exact atomic masses (as they were known at the time) in the margin of a list of the elements, and then wrote out separate cards for each of the elements with the atomic mass and other chemical and physical properties. Using these cards, Mendeleev played “chemical solitaire” for several hours, finally copying to a sheet of paper the arrangement he had worked out with the cards. With slight modification, this became Mendeleev’s first Periodic Table of the Elements.
Periodic refers to the repeating pattern of certain properties of the elements when properly arranged. A horizontal row of elements on the periodic table is known as a period. Family is a concept of “same.” Families are present in vertical columns; so that each element has the same value. Scientists originally thought that weight was a family concept, even though the weights were not the same for every element. They found if you added the top and bottom element weight in a family and divided it by two, it always gave the weight of the element in the middle of that column. This organization of the elements into a logical table is perhaps one of the greatest achievements in the history of science. Other chemists had developed tables of the elements, but Mendeleev’s table was different because he left gaps for several elements yet to be found based on the patterns and trends he discovered. He even accurately predicted the properties of these missing elements!
The purpose of this activity is to arrange nine elements from the periodic table without their name or atomic number.
Periodic table sheet
This laboratory activity is considered nonhazardous. Please follow all laboratory safety guidelines.
Student Worksheet PDF