Homework 1-18-11

When is water the smallest?
Water is smallest when it is at liquid form at room temperature

What happens when salt is added to the water?
When salt is added to the water it takes a lot longer for the water to completely freeze.

Does the amount of salt added affect the freezing?
Yes, the more salt in the water the longer it take for the water to freeze.

For the experiment I had 3 plastic cups with 1 cup of water in each cup.  I let the water sit at room temperature for 1 hour. The water's temperature was 16C.  I marked the cups at the water level.
Cup 1- Water
Cup 2- Water with 1 shake of salt
Cup 3- Water with 1 spoonful of salt
I placed all 3 cups into the freezer. The freezers temp was -15 C.  I left the cups in the freezer for 7 hours.  When I checked the cups the water was frozen in all the cups except for cup 3, that was the cup with a spoonful of salt. Cup 3 had a small layer of non-melted water sitting on top of the ice.  I noticed that the plastic cups were pushed out on the sides. 

(I had picture of my experiment but I was unable to get them to load onto my computer)