Add the dry ice to the mixture and stir frequently to prevent the dry ice from clumping.
Continue to stir until the dry ice has dissolved.
To make Yeast Carbonated Root Beer:Add the sugar and the root beer extract to 11 cups warm water. Add 1 cup of warm water to 1 Tablespoon of yeast. Add the contents together and mix thoroughly. Pour the mixture into clean bottles leaving an inch of space. Let them sit at room temperature for four days. After four days place them in the fridge until they are used.