Materials: Twist™, ice
cubes, salt, plastic
Skills: Observation, Physical change,
1. Explain to students they will investigate how salt
2. Use Twist to
view of an
cube's surface and
of salt crystals.
the salt and ice.
3. Place two ice cubes on a plate. Ask students to predict
what will happen when salt is placed on one of
the ice cubes and write predictions on the attached
4. Sprinkle some
above the salted
ice cube and have
one minute. Take
snapshots of both
ice cubes and label
them salted 1 minute and unsalted
1 minute. Show students the pictures and have students discuss and write what they see.
5. Repeat the process of sprinkling salt on one ice cube. Have students use Twist to collect pictures of both ice cubes after four and eight minutes have passed. Have students record predictions and observations about what the ice cubes look like at each interval. Students generate conclusions about the effects of salt on ice after eight minutes.
6. Show the Twist snapshots taken at different intervals
to students and have them place the pictures in
sequential order. Ask them to justify their ordering
based on details from the pictures. Students present
their findings to the class.
7. Have students add the variables of heat and water
to the experiment to determine if blowing on ice or
placing warm water on ice will have the same effect
as the salt.