Exam 18: Electrochemistry

Given: Ag⁺(aq)+ e^- → Ag(s)E° = +0.799 V AgI(s)+ e^- → Ag(s)+ I^-(aq)E° = -0.152 V Ni²⁺(aq)+ 2 e^- → Ni(s)E° = -0.267 V Which of the following reactions should be spontaneous under standard conditions? I.2 AgI(s)+ Ni(s)→ 2 Ag(s)+ 2 I^-(aq)+ Ni²⁺(aq) II.Ag+(aq)+ I^-(aq)→ AgI(s)

Which is most often used in the laboratory to measure pH?

For a galvanic cell that uses the following two half-reactions, Cr₂O₇^2-(aq)+ 14 H⁺(aq)+ 6 e^- → 2 Cr³⁺(aq)+ 7 H₂O(l) Pb(s)→ Pb²⁺(aq)+ 2 e^- How many moles of Pb(s)are oxidized by one mole of Cr₂O₇^2-?

Consider the half-reaction: MnO₄^-(aq)+ 8 H⁺(aq)+ 5 e- → Mn²⁺(aq)+ 4 H₂O(l).The formation of MnO₄^- from Mn²⁺ occurs most readily when the solution is

The two half-reactions that are used in the direct methanol fuel cell are shown below. I.2 CH₃OH(aq)+ 2 H₂O(l)→ 2 CO₂(g)+ 12 H⁺(aq)+ 12 e^- II.3 O₂(g)+ 12 H⁺(aq)+ 12 e^- → 6 H₂O(l) The electrode at which half-reaction I occurs is the ________ at which ________ is oxidized,and half-reaction II occurs at the ________ at which ________ is reduced.

What is the relationship between the standard cell potentials,E°,for the following two galvanic cell reactions? I.2 Ag⁺(aq)+ Sn²⁺(aq)→ Sn⁴⁺(aq)+ 2 Ag(s) II.2 Ag(s)+ Sn⁴⁺(aq)→ Sn²⁺(aq)+ 2 Ag⁺(aq)

O₂(g)+ 4 H⁺(aq)+ 4 e^-→ 2 H₂O(l)E° = +1.23 V I₂(s)+ 2 e^- → 2 I^-(aq)E° = +0.54 V 2 H₂O(l)+ 2 e^- → H₂(g)+ 2 OH^-(aq)E° = -0.83 V Mg²⁺(aq)+ 2 e^- → Mg(s)E° = -2.37 V Based on the data above,electrolysis of an aqueous solution of MgI₂,with inert electrodes,is expected to produce

Consider the galvanic cell shown below. -Identify the anode and cathode,and indicate the direction of Na⁺ ion and NO₃^- ion flow from the salt bridge.

Given that E°_red = -0.26 V for Ni²⁺/Ni at 25°C,find E° and E for the concentration cell expressed using shorthand notation below. Ni(s)∣ Ni²⁺(aq,1.0 × 10^-5 M)∣∣ Ni²⁺(aq,0.100 M)∣ Ni(s)

In a galvanic cell,the half-reaction H₂(g)+ 2 OH^-(aq)→ 2 H₂O(l)+ 2 e^- is

-The cell reaction 2 Fe³⁺(aq)+ Zn(s)→ Zn²⁺(aq)+ 2 Fe²⁺(aq)occurs in the galvanic cell shown above.Which would be the most appropriate choices for the solid electrode in half-cell (A)and in half-cell (B)?

According to the balanced chemical equation 5 H₂C₂O₄(aq)+ 2 MnO₄^-(aq)+ 6 H⁺(aq)→ 10 CO₂(g)+ 2 Mn²⁺(aq)+ 8 H₂O(l) 0.875 grams of oxalic acid,H₂C₂O₄ will react with ________ moles of permanganate,MnO₄^-.

For the galvanic cell that uses the reaction 2 Al(s)+ 3 Ni²⁺(aq)→ 2 Al³⁺(aq)+ 3 Ni(s) the value of n in the relationship ΔG° = -nFE° is ________.

Chromium can be electroplated from an aqueous solution containing sulfuric acid and chromic acid,H₂CrO₄.What current is required to deposit chromium at a rate of 1.25 g/min?

Based on the half-reactions and their respective standard reduction potentials below,what is the standard cell potential for the reaction that is expected to occur? Fe³⁺(aq)+ e^- → Fe²⁺(aq)0.77 V Sn⁴⁺(aq)+ 2 e^- → Sn²⁺(aq)0.15 V Pb²⁺(aq)+ 2 e^- → Pb(s)-0.13 V

Based on the half-reactions and their respective standard reduction potentials below,the standard cell potential for the reaction that is expected to occur is ________ V. Ag⁺(aq)+ e^- → Ag(s)0.80 V 2 H⁺(aq)+ 2 e^- → H₂(g)0.00 V Cd²⁺(aq)+ 2 e^- → Cd(s)-0.40 V

The gas OF₂ can be produced from the electrolysis of an aqueous solution of KF,as shown in the equation below. OF₂(g)+ 2 H⁺(aq)+ 4 e^- → H₂O(l)+ 2 F^-(aq)E° = +2.15 V Using the given standard reduction potential,calculate the amount of OF₂ that is produced,and the electrode at which the OF₂ is produced,upon the passage of 0.240 faradays through an aqueous KF solution.

In a galvanic cell,the half-reaction MnO₄^-(aq)+ 8 H⁺(aq)+ 5 e^- → Mn²⁺(aq)+ 4 H₂O(l)is

Determine the number of water molecules necessary to balance the reduction half reaction of that occurs in an acidic solution.

What is the value of the equilibrium constant,K for a redox reaction involving the transfer of 6 mol of electrons if its standard potential is 0.043?