13-3

Question 1

As the concentration of the nonvolatile solute increases…

Answer 1

fewer solvent molecules are at the surface and can escape to the vapor phase. Since only solvent contributes to the pressure (solute is nonvolatile) the vapor pressure over solution will decrease.​

Question 2

the vapor pressure of a solution is ____ compared to a pure solvent

Answer 2

the vapor pressure of a solution is lower than that of the pure solvent.​

Question 3

Semipermeable membrane will

Answer 3

let water pass through the membrane. In order to make the vapor pressures equal, water molecules will move right. As the result, PR will up.

Question 4

osmosis definition

Answer 4

The movement of water molecules through a semipermeable membrane

Question 5

As the level of solution on the right increases

Answer 5

the pressure of liquid column on the right (not the vapor pressure), which is proportional to the column height (recall Ch.10), increases. The excess pressure will at some point stop the movement of water molecules. That pressure is called the osmotic pressure.​

Question 6

If two solutions separated by a semipermeable membrane have the same osmotic pressure (are isotonic),

Answer 6

no osmosis will occur.

Question 7

water always moves

Answer 7

from the solution with lower π (less solute, more water) to the solution with higher π (more solute, less water)

Question 8

If stored in a hypertonic solution (πsolution > πblood)…

Answer 8

red blood cells will shrivel as water leaves the cell. This process is called crenation.​ This is why intravenous (IV) solutions MUST be isotonic to blood.​

Question 9

If stored in a hypotonic (πsolution < πblood) solution…

Answer 9

red blood cells will grow as water enters the cells, until the cells burst. This process is called hemolysis.​ This is why intravenous (IV) solutions MUST be isotonic to blood.​