POE (Predict:Observe:Explain)

What Happens to Dry Ice in the Sun?

Introduction to Dry Ice and Prediction Activity

• The experiment begins with a block of dry ice, emphasizing its unique properties compared to regular ice. Participants are encouraged to predict what will happen when it is left in the sun for one hour using a P-O-E (Predict, Observe, Explain) strategy.

• The instructions highlight the importance of writing down predictions and explanations, fostering engagement and critical thinking about the sublimation process.

Observations After One Hour

• Upon returning after an hour, there is no visible trace of the dry ice. This prompts questions about its whereabouts and encourages participants to record their observations.

• The disappearance of dry ice is attributed to sublimation—a process where solid carbon dioxide transitions directly into gas without becoming liquid.

Explanation of Sublimation Process

• Under normal atmospheric pressure, CO2 evaporates directly into a gaseous state, which is why dry ice is often referred to as "the ice that never melts."

• The discussion emphasizes the effectiveness of the P-O-E method for making predictions about uncertain outcomes. It encourages creativity and judgment skills regardless of whether initial predictions were correct.