Temperature and thermochromic materials
What temperature?
Purpose is to review and assess skill with the use of a thermometer and focus attention on collecting accurate information according to the purpose of the situation. Also, to become familiar with thermochromic sheets and see how the color changes as the temperature of the sheet changes and how similar and different they might be.
Thermochromic sheets
Temperature change will turn this black, liquid crystal plastic square to red, orange, green, and blue and each color represents a different temperature. The sheets can be used over and over again. Ones I bought were about 4" x 4" square and mounted on foam. I cut them into smaller pieces for each pair of learners to explore. Samples below:
Room temperature
Heated a bit
One source Arbor scientific.
Temperature exploration
Materials
Thermochromic sheets (available from science distributors), hot and cold water, containers, and thermometers.
Focus question
How are temperatures measured accurately?
Challenge
Use a thermochromatic sheet to explore how to determine accurate temperatures.
Suggested directions
Immerse the sheet in water and change the temperature of the water and sheet until it is as green (or other color) as you can make it.
Hint:
Mix hot and cold water to find
what temperature will make most of the thermochromic sheet green.
Record the temperature of the water when the sheet is as green as you can make it.
Share the temperatures for different groups and their sheets.
How similar or different are the temperatures?
What is the class average?
How would you decide if a temperature was accurate?
What amount of error would be acceptable?
What other examples of objects have you experienced that change color?