Chapter Two - Water

Question 1

how does water interact with each other?

Answer 1

-van der Waals interactions

Question 2

the strength of dispersion forces increase with _____

Answer 2

molecule size

Question 3

hyrdophilic

Answer 3

water loving

Question 4

hydrophobic

Answer 4

water fearing

Question 5

_____ is responsible for hydrophobicity

Answer 5

entropy

Question 6

amphiphiles form _____ and ______ in water

Answer 6

micelles, bilayers

Question 7

water moves by ____

Answer 7

osmosis

Question 8

when will water reach equilibrium?

Answer 8

-if column of fluid above it exerts same pressure equal to osmotic pressure

Question 9

solutes move by _____

Answer 9

diffusion

Question 10

what ions are present in water?

Answer 10

H+ and OH-

Question 11

in neutral water….

Answer 11

[H+]=[OH-] = 10^-7M

Question 12

acidic solutions:

Answer 12

[H+]>10^-7

Question 13

basic solutions:

Answer 13

[OH-]>-7

Question 14

pH =

pOH =

Answer 14

• log[H+]

- log[OH-]

Question 15

pH + pOH =

Answer 15

14

Question 16

any compound with pKa < 14 is _____ and will ____ in water which will thereby ____ the pH

Answer 16

• acidic
• deprotonate
• lower

Question 17

pH =

Answer 17

pKa + log [A-]/[HA]

Question 18

what is a buffer designed to do?

Answer 18

-resist pH changes

Question 19

How does buffer work?

Answer 19

-maintaining large reserve of both HA and A-

Question 20

What happens when H+ is added to the buffer?

Answer 20

-protonates some of the A- turning them into HA

Question 21

what happens when H+ is added to buffer if both [HA] and [A-] are large?

Answer 21

• net changes relatively small

- pH approximately unchanged