03 States of CO2 (Dry Ice) Science By the Horns

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03 States of CO2(Dry Ice)Science By the Horns

• Summer 2004

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Dry Ice is Solid CO2

• The emphasis for these activities is to observe
  the physical process of phase change of CO2 and
  H2O
• Two important differences are
• CO2 forms a solid at very lower temperatures
  (-78oC), and
• CO2 particles move from solid to gas
  (sublimation) without existing in the liquid
  state.
• As well explore with the Chem Theater both of
  these properties are related to the low
  attraction between molecules.

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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.

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Dry Ice ActivitiesFrom GEMS Dry ice
Investigations

• Introduction to Observing
• Comparing Water Ice and Dry Ice
• Exploring Dry Ice
• Marges Systematic Observations
• Marges Experiments
• Choosing an Investigable Question
• Making an Investigation Plan
• Conducting Investigations
• Sharing Results