Solubility and Equilibria - L4 Flashcards
What is the reaction quotient formula
Q = [B]/[A]
- If more A is added, Q value decreases. So Q<k, meaning that reaction goes to the right to produce more products and vice versa
Rule for change in pressure questions
Find the concentration of the gas c = n/V
c = n (1/V)
Qc for pressue
Qc is proportional to 1/V due to the conc. question, so if V increases Qc decreases
Can an inert gas affect equilibrium?
No because there is no inert gas in a Qc expression
Inert gases can pressurise but does not interact with the molecules
In an expression with equal moles, does changing the pressure affect?
No as the V cancels out in the Qc expression
WHOT
Is this only a case with gases
What is solubility?
How much solute will dissolve in a given volume of solvent
What is a saturated solution?
The max amount of solute has dissolved in a given solvent at temp T
solute (s) ⇌ solute (aq)
What does solubility depend on?
*Nature of solute and solvent
*Temperature
*Pressure (for gaseous states)
What is Ksp
The solubility product of a slightly soluble solid
What does dissolution mean?
Dissolving
Is Ksp mostly one way
Possibly just from solid to ions but not the other way cause it’s a slightly soluble salt
What does a saturated solution mean?
One at ⇌
What do Ksp equations look like?
Just products raised to their stoic powers because the reactant is a pure solid
Equation for Ksp
sˆ2, because Ksp indicates how much of the react dissolves at equlibrium so usually the same no. of ions dissolve eg AgCl
If the ratio is a 2:1 electrolyte, what is the Ksp formula?
4sˆ3
What is a Barium meal?
A liquid used as an x-ray contrast. Ba2+ ions are very toxic to humans but BaSO4 is very insoluble
Gymboard in dental schools
BaCO3
Relationship between ionic product (Qsp) and solubility product (Ksp)
- Qsp < Ksp (no preci is formed as reaction is going to completion)
*Qsp>Ksp (Preci is formed as reactants are being favoured)
The common ion effect
An ion that is a part of the reactants but comes from a different source i.e common to ⇌
It DECREASES the solubility of the product as there are too many ions in the solution
What are SO4 ions crucial for?
Cell growth and other imp porcesses
0.30mol/L in blood
