GENERAL CHEMISTRY II - EXAM 2
WITH CORRECT ANSWERS
Relationships Between Keq and the Chemical Equation - ANSWER --If the reaction is
reversed: Kreverse = 1/Kforward
If the coefficients in the equation are multiplied by a factor: raise the equilibrium constant to
the same factor
If two or more individual chemical equations are added: multiply the corresponding equilibrium
constants by each other to obtain the overall Keq
Dynamic Equilibrium - ANSWER --For a chemical reaction, the condition in which the rate
of the forward reaction equals the rate of the reverse reaction.
Equilibrium Constant (K) - ANSWER --The ratio (at equilibrium) of the concentrations of
the products raised to their stoichiometric coefficients divided by the concentrations of the
reactants raised to their stoichiometric coefficients.
aA+bB↔cC+dD
K=([C]^c[D]^d)/([A]^a[B]^b)=[products]/[reactants]
Relative Size of Keq - ANSWER --If K>>1, reaction proceeds forward; favors products
If K<<1, reaction proceeds a little; favors reactants
If K≈1, reaction proceeds about half way
, Heterogeneous Equilibria Involving Solids and Liquids - ANSWER --The concentrations of
pure liquids and solids remain constant and are therefore excluded from the equilibrium
expression.
Expressing Keq in Terms of Pressure - ANSWER --Kp=Kc(RT)^(∆n)
where Kp is the equilibrium constant with respect to partial pressures in atm, Kc is the
equilibrium constant with respect to concentration, R=0.08206 L·atm/mol·K, T is temperature in
K, and ∆n is the change in number of moles of gas
In an endothermic reaction:
Increasing the temperature causes an endothermic reaction to shift in the direction of the
products; the value of Keq increases.
Decreasing the temperature causes an endothermic reaction to shift in the direction of the
reactants; the value of Keq decreases.
General Properties of Acids - ANSWER --sour taste, ability to dissolve many metals, ability
to turn blue litmus paper red, ability to neutralize bases
HCl - ANSWER --Hydrochloric Acid; a common acid
H₂SO₄ - ANSWER --Sulfuric Acid; a common acid (diprotic acid)
HNO₃ - ANSWER --Nitric Acid; a common acid
HC₂H₃O₂ - ANSWER --Acetic Acid; a common acid
H₃C₆H₅O₃ - ANSWER --Citric Acid; a common acid
WITH CORRECT ANSWERS
Relationships Between Keq and the Chemical Equation - ANSWER --If the reaction is
reversed: Kreverse = 1/Kforward
If the coefficients in the equation are multiplied by a factor: raise the equilibrium constant to
the same factor
If two or more individual chemical equations are added: multiply the corresponding equilibrium
constants by each other to obtain the overall Keq
Dynamic Equilibrium - ANSWER --For a chemical reaction, the condition in which the rate
of the forward reaction equals the rate of the reverse reaction.
Equilibrium Constant (K) - ANSWER --The ratio (at equilibrium) of the concentrations of
the products raised to their stoichiometric coefficients divided by the concentrations of the
reactants raised to their stoichiometric coefficients.
aA+bB↔cC+dD
K=([C]^c[D]^d)/([A]^a[B]^b)=[products]/[reactants]
Relative Size of Keq - ANSWER --If K>>1, reaction proceeds forward; favors products
If K<<1, reaction proceeds a little; favors reactants
If K≈1, reaction proceeds about half way
, Heterogeneous Equilibria Involving Solids and Liquids - ANSWER --The concentrations of
pure liquids and solids remain constant and are therefore excluded from the equilibrium
expression.
Expressing Keq in Terms of Pressure - ANSWER --Kp=Kc(RT)^(∆n)
where Kp is the equilibrium constant with respect to partial pressures in atm, Kc is the
equilibrium constant with respect to concentration, R=0.08206 L·atm/mol·K, T is temperature in
K, and ∆n is the change in number of moles of gas
In an endothermic reaction:
Increasing the temperature causes an endothermic reaction to shift in the direction of the
products; the value of Keq increases.
Decreasing the temperature causes an endothermic reaction to shift in the direction of the
reactants; the value of Keq decreases.
General Properties of Acids - ANSWER --sour taste, ability to dissolve many metals, ability
to turn blue litmus paper red, ability to neutralize bases
HCl - ANSWER --Hydrochloric Acid; a common acid
H₂SO₄ - ANSWER --Sulfuric Acid; a common acid (diprotic acid)
HNO₃ - ANSWER --Nitric Acid; a common acid
HC₂H₃O₂ - ANSWER --Acetic Acid; a common acid
H₃C₆H₅O₃ - ANSWER --Citric Acid; a common acid
