EXPERIMENT 3.2
CREATING A PERIODIC TABLE
PURPOSE:
To model Mendeleev's process by attempting to arrange color cards according to their observed properties of color and intensity.
MATERIALS:
- Color cards found in the student notebook (You can also find a copy to print on the Book Extra site.)
- Scissors
- Glue or tape
QUESTION:
Can you form a periodic table with rows and columns showing a repeating change in properties (color) and increasing atomic mass (shade or color intensity)?
BACKGROUND:
The color of a card represents its properties. For example, you can consider all green color cards to have similar properties. The green color cards will all have different properties from the orange cards (and all other color cards). The shade (intensity) of a color card represents its atomic mass. In other words, a light (lower intensity) green color card represents an element with a lower atomic mass than a dark (higher intensity) green color card.
PROCEDURE:
- Use the interactive simulation below. You will see 24 color cards organized by color families and a periodic table grid with 34 spaces.
- Drag and drop the color cards from the card container into the periodic table grid. Arrange them in 8 columns following the rainbow pattern: red, orange, yellow, green, teal, blue, indigo, violet. The first row should have only 2 cards (positions 1 and 8).
- Within each column, arrange cards by increasing intensity (lighter shades at the top, darker shades at the bottom). This represents increasing atomic mass.
- Notice that you have missing elements - there are 34 grid spaces but only 24 cards. This models Mendeleev's challenge! Predict where the missing elements belong and describe their properties in the form below.
- Use the "Check Arrangement" button to verify your periodic table follows the correct pattern (same colors in columns, increasing intensity down each column).
- Tip: Right-click on any card to return it to its original position. Use the "Reset" button to start over if needed.
- Complete the form below with your predictions about missing elements and your conclusions about periodic patterns.
CONCLUSION:
Were your predictions correct? Explain how the periodic table is a good model for predicting unknown elements and their properties.
INTERACTIVE SIMULATION:
Use this interactive simulation to arrange color cards into a periodic table pattern. Drag and drop the color cards to arrange them by color (property) and intensity (atomic mass).