Conservation of Mass and Volume in Solutions David Fan Mr. Chesbro P-2 1. Look at the class data. Does it appear that mass is conserved when a solution is formed? Why or why not? Mass should be conserved when a solution is formed, since the same amount of solvent and solute are present compared to before, but there might be some deviation due to human error. The system is a closed one, so no matter can get in or out. 2. Why did I show you the demo with the beaker of rocks and salt and what did that have to do with the ethanol + water solution It shows that volume is not conserved because the solute and solvent don’t stack on top of each other like a density column. They mix and occupy each other’s space, so the overall volume is lower than the sum of their volumes 3. Look at the class data and the hint images above. Does it appear that volume is conserved when a solution of two liquid molecules is formed? Why or why not? No. The liquids don’t stack on top of each other. They mix and occupy each other’s space, and so the volume is lower than what one would expect 4. Explain 2 different ways in which the salt could be physically separated from the beaker of rocks so I could you it again. You could filter the solution so that only the salt would pass through into a container, while the rocks stay above the container 5. Watch this video and describe what you saw… http://www.youtube.com/watch? v=84k206qaVRU I saw an experiment that showed that volume is not conserved when a solution is formed, because there are spaces between the particles of the solvent which the solute can fit into two. 1 + 1 ≠ 2

Conservation of Mass and Volume in Solutions

Conservation of Mass and Volume in Solutions David Fan Mr. Chesbro P-2