Textbook Question
Consider the voltaic cell:
d. Indicate the direction of anion and cation flow in the salt bridge
Ch.19 - Electrochemistry
Chapter 19, Problem 51
Make a sketch of the voltaic cell represented by the line notation. Write the overall balanced equation for the reaction and calculate E°cell. Sn(s) | Sn2+(aq) || NO(g) | NO3–(aq), H+(aq) | Pt(s)
Verified step by step guidance1
Identify the anode and cathode components from the line notation. The anode is where oxidation occurs and is represented on the left side of the double vertical lines (||). In this case, Sn(s) | Sn2+(aq) is the anode half-cell, and NO(g) | NO3-(aq), H+(aq) | Pt(s) is the cathode half-cell.
Write the half-reactions for both the anode and cathode. For the anode, the oxidation reaction is Sn(s) → Sn2+(aq) + 2e-. For the cathode, the reduction reaction is NO3-(aq) + 4H+(aq) + 3e- → NO(g) + 2H2O(l).
Balance the overall cell reaction by equalizing the number of electrons transferred in the oxidation and reduction half-reactions. Multiply the anode reaction by 3 and the cathode reaction by 2 to balance the electrons: 3Sn(s) → 3Sn2+(aq) + 6e- and 2NO3-(aq) + 8H+(aq) + 6e- → 2NO(g) + 4H2O(l).
Add the balanced half-reactions to get the overall cell reaction: 3Sn(s) + 2NO3-(aq) + 8H+(aq) → 3Sn2+(aq) + 2NO(g) + 4H2O(l).
Calculate the standard cell potential, Ec°ell, using the standard reduction potentials of the cathode and anode. Ec°ell = Ec°(cathode) - Ec°(anode). Look up the standard reduction potentials for each half-reaction in a table of standard potentials.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Voltaic Cell
A voltaic cell, also known as a galvanic cell, is an electrochemical cell that converts chemical energy into electrical energy through spontaneous redox reactions. It consists of two half-cells, each containing an electrode and an electrolyte. The flow of electrons from the anode to the cathode generates an electric current, which can be harnessed for external use.
Recommended video:
Guided course
01:21
The Electrolytic Cell
Standard Electrode Potential (E°)
The standard electrode potential (E°) is a measure of the tendency of a chemical species to be reduced, measured under standard conditions (1 M concentration, 1 atm pressure, and 25°C). It is expressed in volts and is used to calculate the overall cell potential (E°cell) for electrochemical reactions. The more positive the E° value, the greater the species' ability to gain electrons and undergo reduction.
Recommended video:
Guided course
01:27Standard Cell Potential
Nernst Equation
The Nernst equation relates the cell potential (E) to the standard electrode potential (E°) and the concentrations of the reactants and products involved in the electrochemical reaction. It is given by E = E° - (RT/nF) ln(Q), where R is the gas constant, T is the temperature in Kelvin, n is the number of moles of electrons transferred, F is Faraday's constant, and Q is the reaction quotient. This equation allows for the calculation of cell potential under non-standard conditions.
Recommended video:
Guided course
01:17The Nernst Equation
Related Practice
Textbook Question
Use line notation to represent each electrochemical cell in Problem 43.
Textbook Question
Determine whether or not each redox reaction occurs spontaneously in the forward direction.
a. Ni(s) + Zn2+(aq) → Ni2+(aq) + Zn(s)
b. Ni(s) + Pb2+(aq) → Ni2+(aq) + Pb(s)
c. Al(s) + 3 Ag+(aq) → Al3+(aq) + 3 Ag(s)
d. Pb(s) + Mn2+(aq) → Pb2+(aq) + Mn(s)
Textbook Question
Determine whether or not each redox reaction occurs spontaneously in the forward direction.
a. Ca2+(aq) + Zn(s) → Ca(s) + Zn2+(aq)
b. 2 Ag+(aq) + Ni(s) → 2 Ag(s) + Ni2+(aq)
c. Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s)
d. 2 Al(s) + 3 Pb2+(aq) → 2 Al3+(aq) + 3 Pb(s)