Chapter 13 + 16 - Equilibrium + Ksp Flashcards
What does it mean when K > 1, K < 1, and when K = 1? (ratios) What does this mean?
K>1 means that there will be many more products than reactants at equilibrium; reaction essentially goes to completion
K<1 means that there are more reactants than products at equilibrium; reaction does not occur significantly
K=1 means that the ratio of reactants to products is equal at equilibrium
Define Q
Q= the reaction quotient/”k” at a SPECIFIC TIME (best defined as reaction progress)
What does it mean when Q >k, <k, or = k?
> k system shifts left
< k system shifts right
= k system does not shift, is at equilibrium
What happens when the concentration/pressure of one or more of the products/reactants is zero?
Reaction shift towards the missing component
Homogenous vs. heterogenous equilibria
Homogenous: Same phase (ex. HCN(aq) <–> H+(aq) + CN-(aq)
Heterogeneous: Involves more than one phase
What kind of substances have no impact on the position of heterogeneous equilibrium? Why?
Pure solids and liquids due to having a constant concentration
Kc vs. Kp (not the equation)
Kc - Constant of concentrations of substances
Kp - Constant of partial pressures of concentrations
Equation relating Kc and Kp:
Kp = Kc (RT)^change in n
Reactant-favored vs. product favored (which is right, which is left?
Reactant - position lies to the left
Product - Position lies to the right
When asked for equilibrium concentration/pressure in relation to initial use a…
ICE box
When one or more concentrations/pressures are mentioned but others are not in q question, the values of the unmentioned substances are:
0
Anything divided by 0 is…
infinitely large (undefined)
In the ICE box method _______ (always/never) use coefficients to determine the concentration x values coefficients.
always
What is Ksp? How does it compare to solubility?
Ksp = solubility product
Ksp is the ratio of products:reactants at equilibrium
What is a conjugate?
Anion
Do strong acids form in solution? WHy or why not?
No, because they 100% dissociate they will never associate while in sol’n
What happens when Q>Ksp? When Q<Ksp and Q=Ksp?
Q>Ksp - Precipitation forms
Q<Ksp - No precipitation
Q=Lsp - No precipitate but maximum saturation of ions in sol’n
Pure solids/liquids _____ (do/do not appear) in the equilibrium expression
do not appear
k vs. K (AUTHORS NOTE EDIT)
k = rate constant
K = equilibrium constant, =
K or the equilibrium constant is _____-dependent. Why?
temperature, changing it will give the products and reactants new rates, and thus new concentrations at equilibrium.
What is the effect of catalysts/increasing surface area on equilibrium position?
None, they speed up rate of rxn in BOTH sides, maintaining K
Why do salts like AgCl have the same solubility in acid as they do in water?
Cl- is the conjugate of strong acid, strong acid will not form in water and instant 100% dissociate even if it did
What happens when Q (ion product) is >, <, and = Ksp? Also, what makes Q special?
Q is Ksp but w/initial concentrations
Q> Ksp = precipitation, too many reactants to dissolve
Q< Ksp = no precipitation
Q = Ksp = at equilibrium, MAXIMUM saturation b4 precipitation
Define le chatelier’s principle
a rxn at equilibrium will respond to eligible changes by increasing product or reactant reaction rates
