1. 03 States of CO2 (Dry Ice) Science By the Horns Summer 2004

2. Dry Ice is Solid CO2 The emphasis for these activities is to observe the physical process of phase change of CO 2 and H 2 O; Two important differences are: –CO 2 forms a solid at very lower temperatures (-78 o C), and; –CO 2 particles move from solid to gas (sublimation) without existing in the liquid state. As we’ll explore with the Chem Theater both of these properties are related to the low attraction between molecules.

3. Safety concerns Dry ice should never be touched directly. Do not inhale deeply the gas produced from dry ice. Make sure the room has adequate ventilation. Use dry ice only as directed or approved by instructor. When using a hammer to crush and produce small pieces for student use, be sure to: wear goggles; place dry ice on a solid surface; cover the dry ice with a cloth; handle dry ice pieces with gloves that protect hands from cold.

4. Dry Ice Activities From GEMS “Dry ice Investigations” Introduction to Observing Comparing Water Ice and Dry Ice Exploring Dry Ice Marge’s Systematic Observations Marge’s Experiments Choosing an Investigable Question Making an Investigation Plan Conducting Investigations Sharing Results