Editing Hot Ice (section)

== Demonstration ==

;Preparation:
Prepare the Sodium Acetate Solution: measure out 65mL of the sodium acetate and pour into the volumetric flask. Add water to fill it to the 200mL line, and heat the solution while stirring until all the crystals dissolve into the solution, about 30 minutes. If there is trouble with getting all the crystals to dissolve, then add water in small 3-5mL increments. Once all the crystals have dissolved, add a small pinch more of the crystals and dissolve them into it. Remove the solution from heat and cork it, and allow the solution to cool slowly to room temperature. Keep stored in a chemical cabinet and label it with the date it was prepared.
;Presentation (Stage):
''Prior to presenting, if the solution is crystallized then reheat it on the hot plate for 10-15 minutes to remelt it. Set the solution carefully into a bowl with ice water to cool it. It can be kept in the ice water at the start of the show.''
# Ask the audience of any of them have ever seen stalagmites or stalactites in person. Can anyone guess how they form?
# Show the flask and mention that the solution inside is a super saturated solution. Set out the watch glass with a small seed crystal in the center, and ask the audience What they think might happen if if poured out the solution.
# Carefully start pouring the solution directly on top of the seed crystal. You should see a stalagmite start to form! Try to pour out the entire solution and create a large stalagmite. The solution is very sensitive, so it might crystallize inside the flask as you are pouring!
# Alert the audience that not only did the solution crystallize, but it also heated up as it did so. Why would it heat up? Why did it crystallize?
;Presentation (Hands-on):
''Prior to presenting, if the solution is crystallized then reheat it on the hot plate for 10-15 minutes to remelt it. Set the solution carefully into a bowl with ice water to cool it. It can be kept in the ice water at the start of the show.''
# Show the students the flask, and ask them what the solution inside looks like (most will say water, they might note some slight discoloration). Let a student feel the flask and note that it is currently cold, like the ice water.
# Shake the solution and set it down quickly onto the table. Tell the students to watch the solution. They will see small snowflake crystals form, and from there the whole solution will crystallize in under a minute!
# Ask the same student from before to feel the outside of the container, and ask them if the flask is now warmer or cooler. Why is it warmer? What caused the solution to crystallize?