Solubility Unit III Lesson 1. Solubility is a measure of the maximum amount of solid that will...
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Transcript of Solubility Unit III Lesson 1. Solubility is a measure of the maximum amount of solid that will...
SolubilityUnit IIILesson 1
Solubility is a measure of the maximum amount of solid that will dissolve in a volume of water.
Units: g/L mol/L g/100mL
Or even: mL/L for CO2(g) in water
The unit must have an amount on the top and volume on the bottom!
In order to determine the solubility you must completely fill or saturate the solution!
To saturate the solution you must add weighed portions of the solid to a given volume of water and stir until no more will dissolve. A small amount of excess solid will be present in the saturated solution.
NaCl 10.0 g
Determining The Solubility of NaCl
Take 100 mL of water
Add measured portions of NaCl and stir to dissolve
NaCl
Determining The Solubility of NaCl
NaCl
Determining The Solubility of NaCl
The solution is stirred and it all dissolves
NaCl
Determining The Solubility of NaCl
The solution is stirred and it all dissolves
Na+ Cl-
Amount NaCl Dissolved
10.0 g
Determining The Solubility of NaCl
The solution is stirred and it all dissolvesRate of dissolving > Rate of crystallization
Na+ Cl-
NaCl 10.0 g Amount NaCl Dissolved
10.0 g
Determining The Solubility of NaCl
Add more since the solution is not full
Na+ Cl-
NaCl
Amount NaCl Dissolved
10.0 g
Determining The Solubility of NaCl
Na+ Cl-NaCl
Amount NaCl Dissolved
10.0 g
Determining The Solubility of NaCl
The solution is stirred and it all dissolves
Na+ Cl-NaCl
Amount NaCl Dissolved
10.0 g
Determining The Solubility of NaCl
The solution is stirred and it all dissolves
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g
Determining The Solubility of NaCl
The solution is stirred and it all dissolvesRate of dissolving > Rate of crystallization
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g
NaCl 10.0 g
Determining The Solubility of NaCl
Add more since the solution is not full
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g
NaCl
Determining The Solubility of NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g
NaCl
Determining The Solubility of NaCl
The solution is stirred and it all dissolves
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g
NaCl
Determining The Solubility of NaCl
The solution is stirred and it all dissolves
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g
Determining The Solubility of NaCl
The solution is stirred and it all dissolvesRate of dissolving > Rate of crystallization
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g
NaCl 3.0 g
Determining The Solubility of NaCl
Add more since the solution is not full
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g
NaCl
Determining The Solubility of NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g
NaCl
The solution is stirred and it all dissolves
Determining The Solubility of NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g
NaCl
The solution is stirred and it all dissolves
Determining The Solubility of NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g 3.0 g
The solution is stirred and it all dissolvesRate of dissolving > Rate of crystallization
Determining The Solubility of NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g 3.0 g
NaCl 1.0 g
Determining The Solubility of NaCl
Add more since the solution is not full
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g 3.0 g
Determining The Solubility of NaCl
NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g 3.0 g
Determining The Solubility of NaCl
NaCl
Na+ Cl-
Amount NaCl Dissolved
10.0 g10.0 g10.0 g 3.0 g
33.0 g/100 mL
Determining The Solubility of NaCl
NaCl(s)
Rate of dissolving = Rate of crystallization
A bit of solid (1 g) sits on the bottom
The solution is stirred and it does not dissolve!The solution is full or saturated.
Amount NaCl Dissolved
10.0 g10.0 g10.0 g 3.0 g
33.0 g/100 mL
The solution is stirred and it does not dissolve!The solution is full or saturated.
Determining The Solubility of NaCl
Na+ Cl-
NaCl(s)
Rate of dissolving = Rate of crystallization
A bit of solid sits on the bottomThis tells you that the solution is saturated and that it is in equilibrium
Calculate the solubility in units of g/L and mole/L.
Solubility = 33.0 g0.100 L
= 330. g/L
s = molar solubility = the molarity to saturate
= 33.0 g x 1 mole 58.5 g
0.100 L
= 5.60 M
33.0 g/100 mL
Na+ Cl-
NaCl(s)
A bit of solid sits on the bottomThis tells you that the solution is saturated and that it is in equilibrium
Since this is an equilibrium lets write the Equilibrium
Equation: NaCl(s) ⇌ Na+ + Cl-
Expression: Keq = [Na+][Cl-] do not count a solid!
Because this Keq is special and based on the solubility of a solid it is called a solubility product or Ksp.Ksp = [Na+][Cl-]
This unit is all about the Ksp and the solubility of saturated solutions.
There are three types of solutions. Unsaturated Contains less than the maximum amount of dissolved solid
Not at equilibrium
Add more solid and it will dissolve
The rate of dissolving > the rate of crystallizing
There are three types of solutions.
Saturated
Contains the maximum amount of dissolved solid
At equilibrium
Add more solid and it does not dissolve
The rate of dissolving is equal to the rate of crystallization
There are three types of solutions.
Supersaturated
Contains more than the usual maximum amount of dissolved solid
Not at equilibrium
Add more solid and more solid precipitates
The rate of dissolving is less than the rate of crystallization
What we just calculated was exact solubility. The data book page 4 gives us relative solubility.
High Solubility means > .1 MLow Solubility means .1M Classify as high or low solubility. Na3PO4
What we just calculated was exact solubility. The data book page 4 gives us relative solubility.
High Solubility means > .1 MLow Solubility means .1M Classify as high or low solubility. Na3PO4 High
H2SO4
What we just calculated was exact solubility. The data book page 4 gives us relative solubility.
High Solubility means > .1 MLow Solubility means .1M Classify as high or low solubility. Na3PO4 High
H2SO4 High
Ca(NO3)2
What we just calculated was exact solubility. The data book page 4 gives us relative solubility.
High Solubility means > .1 MLow Solubility means .1M Classify as high or low solubility. Na3PO4 High
H2SO4 High
Ca(NO3)2 High
CaSO4
What we just calculated was exact solubility. The data book page 4 gives us relative solubility.
High Solubility means > .1 MLow Solubility means .1M Classify as high or low solubility. Na3PO4 High
H2SO4 High
Ca(NO3)2 High
CaSO4 Low
FeSO4
What we just calculated was exact solubility. The data book page 4 gives us relative solubility.
High Solubility means > .1 MLow Solubility means .1M Classify as high or low solubility. Na3PO4 High
H2SO4 High
Ca(NO3)2 High
CaSO4 Low
FeSO4 High
Classify as high or low solubility. Ag2SO4
Classify as high or low solubility. Ag2SO4 low
CuSO4
Classify as high or low solubility. Ag2SO4 low
CuSO4 high
CuCl2
Classify as high or low solubility. Ag2SO4 low
CuSO4 high
CuCl2 high
CuCl
Classify as high or low solubility. Ag2SO4 low
CuSO4 high
CuCl2 high
CuCl low BaS
Classify as high or low solubility. Ag2SO4 low
CuSO4 high
CuCl2 high
CuCl low BaS high K2CO3
Classify as high or low solubility. Ag2SO4 low
CuSO4 high
CuCl2 high
CuCl low BaS High K3CO3 high
Ionic Solutions Molecular Solutions NaCl(aq) C6H12O6(aq) metal
Ca(OH)2(aq) C12H22O11(aq) nonmetal
(NH4)3PO4(aq) CH3OH(aq)
Ca(CH3COO)2(aq) O2(aq)
H2SO4(aq) N2H4(aq)
Conduct electricity Do not conduct electricity
Write dissociation (ionic) or dissolving (molecular) equations for the first six compounds to show how each dissolves in water.The first five are solids and the sixth one is a liquid.
NaCl(s) Na+ + Cl-
C6H12O6(s) C6H12O6(aq)
Ca(OH)2(s) Ca2+ + 2OH-
C12H22O11(s) C12H22O11(aq)
(NH4)3PO4(s) 3NH4+ + PO4
3-
CH3OH(l) CH3OH(aq)
Equilibrium Expressions for Saturated Solutions
Write the equation for equilibrium present in a saturated solution of Al2(SO4)3 solution.
Al2(SO4)3(s) ⇌ 2Al3+ + 3SO42-
Write the equilibrium expression or solubility product
Solubility Product = Ksp = [Al3+]2[SO42-]3
Equilibrium Expressions for Saturated Solutions
Write the equation for equilibrium present in a saturated solution of Al2(SO4)3 solution.
Ca3(PO4)2(s) ⇌ 3Ca2+ + 2PO43-
Write the equilibrium expression or solubility product
Solubility Product = Ksp = [Ca2+]3[PO43-]2