Lecture 5 (Ch. 13): BP & FP Elevation/Depression, Osmosis

Question 1

normal boiling point

Answer 1

-temp when liquid VP equals 1 atm pressure

Question 2

freezing point

Answer 2

-temp when crystals of pure solvent form

Question 3

what does ΔT stand for?

Answer 3

Tsoln - Tpure solvent

Question 4

what does Kb and Kf stand for

Answer 4

-solvent molal boiling/freezing point elevation/depression constant

Question 5

osmosis

Answer 5

-net movement of solvent molecules across a semipermeable membrane

Question 6

how does movement occur during osmosis?

Answer 6

-always occurs from high solvent to low solvent (less solute to more solute)

Question 7

osmotic pressure (π)

Answer 7

-pressure required to stop osmosis

Question 8

osmotic pressure equation and units

Answer 8

π=iMRT OR π=i(n/V)RT
π: osmotic pressure(atm)
i: # solute particles in soln
V: volume (L)
R: 0.08206
T: temp (K)
M: molarity

Question 9

isotonic

Answer 9

• soln of equal conc.

- cell size is constant

Question 10

hypertonic

Answer 10

• soln of higher conc.
• water leaves the cell
• cell size shrinks

Question 11

hypotonic

Answer 11

• soln of lower conc.
• water enters the cell
• cell expands