Today students complete their investigation of ice. They start by checking the bottles to answer whether weight and volume change as ice melts. At this point students should have substantial evidence for answering the question, What changes and what stays the same as ice melts? at the visible level. To learn about what is happening at a very much smaller scale, the particle level, students observe the Particle Magnifier, a computer model that introduces scientists' understanding that all matter is made of tiny particles (atoms or molecules). As the ice is warmed, students see the motion of individual particles increase to the point where the bonds holding the particles locked in position in the solid begin to break and reform. This allows the particles to slide past and collide with one another as the ice is transformed to water.

By the end of this session students will understand that, as ice melts, the weight of a sample remains the same, the volume decreases, and the kind of matter - water - remains the same. They will have been introduced to the particle model of matter and considered how the model helps to explain the transformation of a solid to a liquid.

Learning Goals

• Understand that liquid water and ice are the same kind of matter
• Become familiar with the particle model of matter to explain transformations of water

Sequence of experiences
1. Explore bottles	Pairs	10 Mins
2. Use data	All Class	5 Mins
3. Introduce Particle Magnifier (Water)	All Class	15 Mins
4. Make meaning	All Class	15 Mins

Materials and Preparation

Preparation:

• Read The Particle Magnifier (See Resource Quick Links)
• Explore the Particle Magnifier (Water)
  [Launch Particle Magnifer (Water) in a new window]

For the class:

• Post the investigation question in a place where all students can see it.
• Post the class chart, "Comparing Ice and Water"; created in Investigation 10.
• Post the class table, "Transforming Water to Ice and Ice to Water"; created in Investigation 11.
• The Particle Magnifier (Water), using a classroom computer and projector or Smart Board.

For each group:

• 1 digital scale
• 2 plastic bottles of water, from the last investigation