Day 4: Solutions and Kinetics

Question 1

Supersaturated

Answer 1

More solute is dissolved into the solvent than is possible. Achieved at high temperatures

Question 2

Molarity

Answer 2

mol solute/L solution

Question 3

Molality

Answer 3

mol solute/kg solvent

Question 4

mole fraction

Answer 4

mol solute/ total moles

Question 5

Molarity = Molality

Answer 5

in dilute solutions in water

Question 6

Solubility rules

Answer 6

1. All Group 1 metal, NH4+,NO3-, CLO4-, C2H3O2- (acetate) salts are soluble
2. Most Ag+, Pb+, and Hg2^2+ salts are insoluble

Question 7

Phase solubility in liquids rules

Answer 7

1. Solids are more soluble at high temperatures
2. Gases are less soluble at higher temperatures (greater chance of escaping)
3. Gases are more soluble at high pressures

Question 8

Colligative properties

Answer 8

changes proportionally to concentration of solute.

must be different from solvent

Question 9

van’t Hoff factor (i)

Answer 9

how may ions and particles are formed (on an average) in a solution

Question 10

Freezing point depression

Answer 10

Change in freezing temperature = -iKfm

Question 11

Boiling pt. Elevation

Answer 11

change in boiling temperature = iKbm

Question 12

Vapor pressure Depression(Raoult’s Law)

Answer 12

Pa=XaPtotal

You need pure property vapor pressure #

Question 13

Osmotic Pressure

Answer 13

π = iMRT

Question 14

Collision Theory for chemical reactions to occur

Answer 14

1. Collision
2. Proper orientation
3. Sufficient Energy
4. High temperature high collision frequency, high percentage of high energy collisions

Question 15

State function is independent of

Answer 15

pathway

Question 16

Rxn coordinate diagrams

Answer 16

plot energy as it moves from reactants to products

Question 17

Rate determining step

Answer 17

tallest peak is the rate determining step (slow step)

Question 18

Catalyst

Answer 18

speeds up a reaction by lowering the activation energy by providing an alternate mechanism (pathway) for the reaction to occur

Present in reactants then products

Question 19

Rate Laws

Answer 19

Allows for prediction
Rate = k[A]^x[B]^(y) --> order 
Rate = k[A]^0= k
Rate = k[A]^1 = proportional
Rate k[A]^2 =proportional

Question 20

Elementary Reaction

Answer 20

use co-eff. in front of reactants part of a mechanism

Question 21

Solids and liquids in rate laws

Answer 21

are included

Question 22

Intermediate

Answer 22

present in products then reactants

Question 23

Rate increases with

Answer 23

increase in temperature
increase in the number of reactants
decrease in energy

Question 24

K constant increases with

Answer 24

increasing temperature

decreasing energy