WorksheetsAP Chemistry Equilibrium
Total questions: 15
Worksheet time: 15mins
An aqueous equilibrium mixture of CoCl4 , CoBr4 , Cl-, and Br- is present in a flask at 25°C. Which action below will change the value of the equilibrium constant from that which currently describes the concentration relationships of the four species above?
add more Cl- to the solution
add more CoBr42- to the solution
put the flask into an 80°C water bath
add more Br- to the solution
add more CoCl42- to the solution
The reaction quotient for a system is 729. If the equilibrium constant for the system is 36, what will happen as equilibrium is approached?
There will be a net gain in product.
There will be a net gain in reactant.
There will be a net gain in both product and reactant.
There will be no net gain in either product or reactant.
The equilibrium constant will decrease until it equals the reaction quotient.
The diagram above represents H2(g) and N2(g) in a closed container. Which of the following diagrams would represent the results if the reaction shown below were to proceed as far as possible?
N2(g) + 3H2(g) ↔ 2NH3(g)
N2O4(g) 2NO2(g)
N2O4(g) decomposes into NO2(g) according to the equation above. A pure sample of N2O4(g) is placed into a rigid, evacuated, 0.500 L container. The initial pressure of the N2O4(g) is 760 atm. The temperature is held constant until the N2O4(g) reaches equilibrium with its decomposition products. The figure below shows how the pressure of the system changes while reaching equilibrium.Which diagram is an appropriate description of the partial pressure of N2O4(g) when N2O4(g)
is rapidly injected, at time = 0, into the container after equilibrium is established?
What change was made to the equilibrium system at 15 minutes and what impact did this have on the system?
F2(g) was added and the reaction shifted forward.
F2(g) was added and the reaction shifted in reverse.
F2(g) was removed and the reaction shifted forward.
F2(g) was removed and the reaction shifted in reverse.
CO2(g) was added and the reaction shifted forward.
Given the following information, which of the statements is true:
H+ is incapable of being oxidized or reduced
Sn2+ is the weakest oxidizing agent
Ni(s) is the strongest oxidizing agent
Li(s) is the strongest reducing agent
Li+(aq) is the strongest reducing agent
Find the standard reduction potential for the reaction: In+3 + 3e- → In
0.34 V
–0.34 V
1.02 V
–1.02 V
0.00 V
Consider an electrochemical cell based on the reaction: 2H+(aq) + Sn(s) → Sn2+(aq) + H2(g) Which of the following actions would not change the measured cell potential?
lowering the pH in the cathode compartment
addition of more tin metal to the anode compartment
increasing the tin (II) ion concentration in the anode compartment
increasing the pressure of hydrogen gas in the cathode compartment
any of these things will increase the measure cell potential
2N2O5 (g) → 2N2 (g) + 5O2 (g)
Dinitrogen pentoxide decomposes in a first- order reaction with a half-life of 7 minutes at 230°C according to the equation above.
If N2O5 is added to an evacuated flask to a pressure of 800 torr at 230°C, what is the total pressure in the flask after 14 minutes?
200 torr
800 torr
1400 torr
2300 torr
4200 torr
An unknown acid is dissolved in 25 mL of water and titrated with 0.100 M NaOH. The results are shown in the titration curve above. Which of the following could be the unknown acid?
Fluoroacetic acid, pKa = 2.6
Glycolic acid, pKa = 3.8
Propanoic acid, pKa = 4.9
Hypochlorous acid, pKa = 7.5
Boric acid, pKa = 9.3
A molecular solid coexists with its liquid phase at its melting point. The solid-liquid mixture is heated, but the temperature does not change while the solid is melting. The best explanation for this phenomenon is that the heat absorbed by the mixture
is lost to the surroundings very quickly
is used in overcoming the intermolecular attractions in the solid
is used in breaking the intramolecular bonds within the molecules of the solid
causes the nonbonding electrons in the molecules to move to lower energy levels
Which of the following substances is a strong electrolyte when dissolved in water?
Sucrose
Ethanol
Sodium nitrate
Acetic acid
Ammonia
Which one of the following cannot be determined when studying the thermodynamics of a reaction?
the speed of a reaction.
the direction of a reaction
the extent of a reaction
in which direction a reaction is spontaneous
the temperature at which a reaction will be spontaneous.
Which of the following is true?
Processes that are spontaneous in one direction are spontaneous in the opposite direction.
Processes are spontaneous because they occur at an observable rate.
Spontaneity can depend on the temperature.
All of these statements are true.
Gibb's Free Energy is equal to the inverse of Keq.
Consider the following equilibrium reaction: @@ ext{N}_2(g) + 3 ext{H}_2(g) ightleftharpoons 2 ext{NH}_3(g) .Iftheconcentrationof ext{N}_2@@ is increased, what will be the effect on the equilibrium position?
A) The equilibrium will shift to the right, favoring the formation of NH3 .
B) The equilibrium will shift to the left, favoring the formation of N2 and H2 .
C) The equilibrium will remain unchanged.
D) The equilibrium constant will increase.
