2. Push the "Play" button and watch the video introduction.
3. Once you reach the simulation page, choose "sodium chloride" and set the amount of solute as 1 mol (see example to the right). Press the "play" button and watch the simulation until the temperature reading (upper right corner) remains constant or until the simulation stops.
Record this temperature in the data table below.
4. Repeat step 3 two more times, changing the amount of solute to 2 moles and then to 3 moles.
Chemical
O sodium chloride
• calcium chloride
Amount of Solute a 1 mol
DATA TABLE PART 1: NaCl in Water
Moles of Naci used
1.0
2.0
3.0
Freezing point of solution, "C
-3.75
-7.75
-11.28
QUESTIONS PART 1
1. What happens to the NaC crystal as It comes in contact with the water molecules in the Ice?
2. Look at your data table and the graph in the simulation. What happens to the freezing point of water as the number of moles of solute Increases?
1. The NaCl crystal dissolves in the water molecules in the ice, breaking into ions and becoming a part of the solution.
2. As the number of moles of solute increases, the freezing point of water decreases. This is known as freezing point depression, where the presence of solute particles disrupts the formation of ice crystals, lowering the freezing point of the solution.