35635 Chemistry Practice Problems

Exercise 41. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine ε° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. MnO4 - + 8H + 5e-  → Mn 2+ + 4H2O      ε° = 1.51 V 

    IO4 - + 2H + + 2e- → IO3 - + H2O              ε° = 1.60 V

Calculate ΔG° and K at 25°C for the reaction above.

Watch Solution

Exercise 41. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine ε° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

a. Cl2 + 2e- → 2Cl -        ε° = 1.36 V 

    Br2 + 2e- → 2Br -       ε° = 1.09 V

Calculate ΔG° and K at 25°C for the reaction above.

Watch Solution

Exercise 37. Sketch the galvanic cells based on the following overall reactions. Show the direction of electron flow, and identify the cathode and anode. Give the overall balanced equation. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. Cu 2+(aq) + Mg(s) ⇌ Mg 2+(aq) + Cu(s)

Calculate ΔG° and K at 25°C for the reaction above.

Watch Solution

76

Exercise 42. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine ε° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. Mn 2+ + 2e- → Mn                   ε° = —1.18 V
    Fe 3+ + 3e- → Fe                     ε ° = —0.036 V

Calculate ΔG° and K at 25°C for the reaction above.

Watch Solution

76

Exercise 38. Sketch the galvanic cells based on the following overall reactions. Show the direction of electron flow, the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. Zn(s) + Ag +(aq) ⇌ Zn 2+(aq) + Ag(s)

Calculate ΔG° and K at 25°C for the reaction above.

Watch Solution

Consider a concentration cell similar to the one shown below, except that both electrodes are made of Ni and in the left-hand compartment [Ni2+] = 1.0 M. Calculate the cell potential at 25°C when the concentration of Ni2+ in the compartment on the right has each of the following values.

e. Calculate the potential when both solutions are 2.5 M in Ni  2+.

For each case, also identify the cathode, anode, and the direction in which electrons flow.

Watch Solution

Consider a concentration cell similar to the one shown below, except that both electrodes are made of Ni and in the left-hand compartment [Ni2+] = 1.0 M. Calculate the cell potential at 25°C when the concentration of Ni2+ in the compartment on the right has each of the following values.

d. 4.0 X 10 -5 M

For each case, also identify the cathode, anode, and the direction in which electrons flow.

Watch Solution

Consider a concentration cell similar to the one shown below, except that both electrodes are made of Ni and in the left-hand compartment [Ni2+] = 1.0 M. Calculate the cell potential at 25°C when the concentration of Ni2+ in the compartment on the right has each of the following values.

c. 0.10 M

For each case, also identify the cathode, anode, and the direction in which electrons flow.

Watch Solution

Consider a concentration cell similar to the one shown below, except that both electrodes are made of Ni and in the left-hand compartment [Ni2+] = 1.0 M. Calculate the cell potential at 25°C when the concentration of Ni2+ in the compartment on the right has each of the following values.

b. 2.0 M

For each case, also identify the cathode, anode, and the direction in which electrons flow.

Watch Solution

Exercise 42. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine E° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. Mn2+ + 2e- → Mn                        E° = -1.18 V
    Fe3+ + 3e- → Fe                          E° = -0.036 V

Give the standard line notation for the given cell above.

Watch Solution

Exercise 42. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine E° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

a. H2O2 + 2H+ + 2e- → 2H2O        E° = 1.78 V
    O2 + 2H+ + 2e- → H2O2             E° = 0.68 V

Give the standard line notation for the given cell above.

Watch Solution

Exercise 38. Sketch the galvanic cells based on the following overall reactions. Show the direction of electron flow, the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

a. IO3- (aq) + Fe2+ (aq) ⇌ Fe3+ (aq) + I 2 (aq)

Give the standard line notation for the given cell above.

Watch Solution

Exercise 41. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine E° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. MnO4- + 8H+ + 5e- → Mn2+ + 4H2O      E° = 1.51 V
    IO4- + 2H+ + 2e- → IO3- + H2O              E° = 1.60 V

Give the standard line notation for the given cell above.

Watch Solution

Exercise 41. Sketch the galvanic cells based on the following half-reactions. Show the direction of electron flow, show the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation, and determine E° for the galvanic cells. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

a. Cl2 + 2e- → 2Cl          E° = 1.36 V
    Br2 + 2e- → 2Br -         E° = 1.09 V

Give the standard line notation for the given cell above.

Watch Solution

Exercise 37. Sketch the galvanic cells based on the following overall reactions. Show the direction of electron flow, and identify the cathode and anode. Give the overall balanced equation. Assume that all concentrations are 1.0 M and that all partial pressures are 1.0 atm.

b. Cu2+ (aq) + Mg (s) ⇌ Mg 2+ (aq) + Cu (s)

Give the standard line notation for the given cell above.

Watch Solution

Elements 104, 105, and 106 have been named rutherfordium (Rf), dubnium (Db), and seaborgium (Sg), respectively. These elements are synthesized from californium-249 by bombarding with carbon-12, nitrogen-15, and oxygen-18 nuclei, respectively. Four neutrons are formed in each reaction as well.

(a) Write balanced nuclear equations for the formation of these elements.
(b) Write the equations in shorthand notation.

Watch Solution

24.82

Iodine-131 is one of the most important isotopes used in the diagnosis of thyroid cancer. One atom has a mass of 130.906114 amu. Calculate the binding energy

(c) per mole in kJ

Watch Solution

24.82

Iodine-131 is one of the most important isotopes used in the diagnosis of thyroid cancer. One atom has a mass of 130.906114 amu. Calculate the binding energy

(b) per atom in MeV

Watch Solution

24.81

Cobalt-59 is the only stable isotope of this transition metal. One 59Co atom has a mass of 58.933198 amu. Calculate the binding energy

(c) per mole in kJ

Watch Solution

24.81

Cobalt-59 is the only stable isotope of this transition metal. One 59Co atom has a mass of 58.933198 amu. Calculate the binding energy
(b) per atom in MeV

Watch Solution

Lead-206 is the end product of 238U decay. One 206Pb atom has a mass of 205.974440 amu. Calculate the binding energy
(c) per mole in kJ

Watch Solution

Lead-206 is the end product of 238U decay. One 206Pb atom has a mass of 205.974440 amu. Calculate the binding energy

(b) per atom in MeV

Watch Solution

24.79.

Oxygen-16 is one of the most stable nuclides. The mass of a 16O atom is 15.994915 amu. Calculate the binding energy
(c) per mole in kJ

Watch Solution

24.79.

Oxygen-16 is one of the most stable nuclides. The mass of a 16O atom is 15.994915 amu. Calculate the binding energy
(b) per atom in MeV

Watch Solution

Representations of three nuclei (with neutrons gray and protons purple) are shown below. Nucleus 1 is stable, but 2 and 3 are not. 

(a) Write the symbol for each isotope. 


Watch Solution