Lab 3

Question 1

molarity / 1 molar

Answer 1

1 mole + however much solvent to create total of 1 L solution

Question 2

molality / 1 molal

Answer 2

1 mole solute + 1 L solvent

Question 3

why is molal more precise than molar?

Answer 3

molal tells you exact amount of solute and solvent, in molarity amount of solvent is unknown and dependent on volume of solute

Question 4

1 mole meaning

Answer 4

1 mole = avogadros number of particles

Question 5

dissolving glucose vs dissolving water

Answer 5

hydration sphere forms around glucose vs salt dissociates and hydration spheres form around the ions

Question 6

osmolality

Answer 6

total molality of a solution - takes into account dissociation

• for glucose molality = Osm
• for NaCl molality * 2 = Osm

Question 7

blood plasma osmolality

Answer 7

280-300 mOsm

- remember milli = 1000

Question 8

3 isotonic solutions to increase blood volume / hydration

Answer 8

ringers lactate, normal saline, and 5% dextrose aka D5

Question 9

tonicity

Answer 9

relative term comparing the concentration of solutions

Question 10

isotonic

Answer 10

no net movement of water between solutions

Question 11

why is isotonic solution needed for IV??

Answer 11

if not isotonic liquid would move in and out of cells causing swelling and lysing or crenation/shrinking

Question 12

hypotonic

Answer 12

• if hypotonic to cell = net movement of water into cell

- osmotic pressure is less

Question 13

ringer lactate and when given?

Answer 13

• K+, lactate, and Ca2+
• lactate provides a source of energy
• given during conditions that cause hypoxia (low O2) such as sepsis and burns

Question 14

normal saline and how much salt

Answer 14

• 0.9% saline solution that is isotonic to blood plasma

Question 15

D5

Answer 15

5% dextrose, isotonic to blood plasma, given when person cannot consume food by mouth

Question 16

water intoxication

Answer 16

• excessive water consumption –> cells in brain cells –> coma and death

Question 17

effect of hypotonicity on RBC

Answer 17

• water enters cell causing hemolysis and swelling

Question 18

hypertonic effect on cell

Answer 18

• water leaves cell

- osmotic pressure is higher

Question 19

effect of hypertonicity on RBC

Answer 19

• water leaves cell causign shrinking and crenation

Question 20

regulation of blood osmolality (entire flow)

Answer 20

dehydration –> lowered blood volume, osmolality, and pressure –> detection by osmoreceptors in hypothalamus –> stimulation of thirst center of hypothalamus & ADH secreted by posterior pituitary –> increased reabsorption in kidneys –> blood volume increases

Question 21

which of the 3 test tubes was clear vs cloudy and why?

Answer 21

• cells cause reflection of light and make it cloudy
• hypotonic = clear because of lysis of cells
• isotonic = cloudy because of cells
• hypertonic = moderately cloudy since cells are shrunken

Question 22

albumin

Answer 22

protein in blood vessel, increases osmotic pressure and keeps water in blood vessels, without it edema would occur as water goes into interstitial fluid

Question 23

osmotic pressure

Answer 23

ability of something to pull water

Question 24

percentage meaning

Answer 24

grams of substance / 100mL of liquid

Question 25

ADH and vasoconstriction

Answer 25

at high ADH concentration and extreme dehydration ADH causes vasoconstriction which increase blood pressure