Ch. 10 Flashcards
what is equilibrium?
when the forward reaction equals the backwards reaction but only in a CLOSED system
what is the equilibrium constant?
Keq: concentration of products/reactants at equilibrium
what are four things to note about the equilibrium constant?
- the coefficient of each species becomes an exponent
- solid and pure liquids are NOT included
- aqueous solutions are included
- if rxn is gaseous, partial pressures are used for concentrations
what does Keq < 1 mean?
Keq < 1 favors reactants (more reactants are present)
what does Keq > 1 mean?
Keq > 1 favors products (more products are present)
what is the reaction quotient?
conc of products/reactants NOT @ equilibrium
what does Q < Keq mean?
favors products (too much reactants)
what does Q > Keq mean?
favors reactants (too much products)
what is le Chateliers principle?
a system at equilibrium will neutralize any change to go back to equilibrium
according to le chateliers, when you add more reactant, what is favored?
products
according to le chateliers, when you add more products, what is favored?
reactants
according to le chateliers, high pressure and low volume favors what side?
side with less moles (ONLY TRUE FOR GASES)
according to le chateliers, low pressure and high volume favors what side?
side with more moles (ONLY TRUE FOR GASES)
according to le chateliers, adding an inert gas, what occurs to the rxn? a catalyst?
no effect
according to le chateliers, having an endothermic or exothermic does what to the reaction?
an exothermic rxn: heat acts as a product (exo)
an endothermic rxn: heat acts as a reactant (endo)
when does a solution form?
when a substance dissolves and creates a homogenous solution (dissolution)
what is solute?
sugar in tea, less amount
what is solvent?
tea AKA solvation or hydration if solvent is water
if solvent is water, the solution is
aqueous
electrolytes are
free ions that have dissociate in solution
strong electrolyte? weak electrolyte? nonelectrolyte?
strong: dissolves completely
weak: dissolves completely
nonelectrolyte: no dissociation and bonded covalently NOT ionicly
a concentrated solution has
increased solute
a dilute solution has
decreased solute
a saturated solution has
no more solute will dissolve, at eq
reversed dissolution is called
precipitation
what is solubility?
amount of solute that will saturate a solvent
what are the three phase solubility rules?
- solubility of solids in liquids increase with increased temp
- solubility of gases in liquids decrease with increased temp
- solubility of gases in liquids increase with increased pressure
what are the three salt solubility rules?
- all group 1 and ammonium salts are soluble
- all nitrate (NH3), perchlorate (ClO4^-), and acetate (CH₃COO) salts are soluble
- all silver, lead, and mercury salts are insoluble EXCEPT when they are bonded with nitrate, perchlorate, and acetate.
what is solubility constant? ion product?
solubility constant: to which something will dissolve at eq (product/reactant) BUT SOLID NOR LIQUIDS ARE INCLUDED
ion product: reaction quotient for solubility
Qsp < Ksp
more salt can dissolved
Qsp > Ksp
excess salt will precipitate
what is the common ion effect
addition of another salt (common ion) will cause the backward reaction to be favored, theres more “product” present
adding ligands (lewis bases) will have what effect on solubility?
increased solubility
standard delta G < 0 is
spon favors products Keq > 1
standard delta G > 0 is
nonspon favors reactants Keq < 1
low solubility is equal to
smallest Ksp value
