Water Pt.2

Question 1

Bronsted-Lowry Acid

Answer 1

Proton donor

Question 2

Bronsted-Lowry Base

Answer 2

Proton acceptor

Question 3

The exact point at which the titrant reacts completely with the analyte is the equivalence point

Answer 3

the equivalence point (stoichiometric point)

Question 4

Freezing point depression

Answer 4

drop in the max. temp at which a substance freezes

Question 5

Freezing point is easily seen when comparing

Answer 5

pure water and solution freezing temps

Question 6

Boiling point elevation is a result of an increase in the

Answer 6

concentration of a solution when compared to pure water

Question 7

P (Vapor pressure in cmpd/soln) =

Answer 7

(P*)(X)

P*: vapor pressure of volatile cmpd at a certain temp

X : mile fraction of cmpd

Question 8

Raoult’s Law

Answer 8

P(soln) = (Xsol)(P*sol)

P(soln) = solu vapor pressure

Xsol = mole frac. of sol

P* sol = vapor pressure of pure solvent

Question 9

p/p* =

Answer 9

Aw (water activity)

p = vapor pressure of pure water

p* = vapor pressure of water in food

Question 10

%ERH/100

Answer 10

Aw (water activity)

Question 11

Hydration

Answer 11

combined with water to form a hydrate with the water molecule retained in its molecular state

Question 12

Dehydration

Answer 12

process of removing water from a substance or compound

Question 13

Solvent Properties

Answer 13

capable of dissolving another substance without changing chemical form

Question 14

Solution

Answer 14

Physically and homogenous mixture in which the solute is either in an ionic or molecular state of subdivision

Question 15

Hydrolysis

Answer 15

decomposition of a chemical compound by reaction with water

Question 16

If separated from pure water by a semi-permeable membrane water molecules will

Answer 16

pass through the membrane to equalize the concentration (OSMOSIS)

Question 17

Isotonic solutions refer to

Answer 17

two solutions that have equal osmotic pressure

Question 18

Colloids =

Answer 18

mixtures with solid, liquid, or gas suspended (dissolved) in a liquid

Question 19

M1 V1 =

Answer 19

M2 V2

Question 20

Equilibrium constant for water: Keq

Answer 20

[H+][OH-]/[H2O]

Question 21

Living cells have a VERY

Answer 21

narrow range of tolerance for pH i.e. [H+]

Question 22

Water Activity (definition)

Answer 22

ratio of the partial pressure of water in a sample (p) and the vapor pressure of pure water (p0) at the same temperature

Question 23

Utilization of water for food processing

Answer 23

+ Soaking
+ Cleaning
+ Blanching
+ Chilling
+ Cooling
+ Sanitizing