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I NEED HELP PLEASE, THANKS!

Electrochemistry is important in many aspects of daily life.
i. Define voltaic cell.
ii. Fill in the blanks for the drawing of a voltaic cell that’s made with copper/copper (II) nitrate (E° = 0.34 V) and zinc/zinc (II) nitrate (E° = –0.76 V). Briefly explain the role of the salt bridge.
iii. Using the equation E°cell = E°cathode – E°anode, calculate the overall cell potential for the cell.
iiii.
a. _____________
b. _____________
c. _____________
d. _____________
e. _____________
f. _____________
g. _____________
h. _____________

I NEED HELP PLEASE, THANKS! Electrochemistry is important in many aspects of daily-example-1
User Yugi
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2 Answers

5 votes

Answer:a. Electron flow

b. Voltmeter or lightbulb

c. Electron flow

d. Cathode or Cu

e. Cu²⁺(aq) and NO₃⁻(aq)

f. Salt bridge

g. Zn²⁺(aq) and NO₃⁻(aq)

h. Anode or Zn

Step-by-step explanation:

User Lkartono
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3.4k points
6 votes

Answer:

Here's what I get

Step-by-step explanation:

(i) Voltaic cell

A voltaic cell is a device that uses a chemical reaction to produce electrical energy.

(ii) Overall Cell Potential

The standard reduction potentials for the half-reactions are

ℰ°/V

Cu²⁺ + 2e⁻ ⇌ Cu 0.34

Zn²⁺ + 2e⁻ ⇌ Zn -0.76

The half-reaction with the more positive potential is the reduction half-reaction. It is the reaction that occurs at the cathode.

The half-reaction with the more negative potential is the oxidation half-reaction. It is the reaction that occurs at the anode.

We reverse that half-reaction and subtract the voltages to get the cell reaction.

ℰ°/V

Cathode: Cu²⁺ + 2e⁻ ⇌ Cu 0.34

Anode: Zn ⇌ Zn²⁺ + 2e⁻ -0.76

Cell: Zn + Cu²⁺ ⇌ Zn²⁺ + Cu 1.10


\mathcal{E}_{\text{cell}}^(\circ) = \mathcal{E}_{\text{cat}}^(\circ) - \mathcal{E}_{\text{an}}^(\circ) = \text{0.34 V} - \text{(-0.76 V)} = \text{0.34 V} + \text{0.76 V} = \textbf{1.10 V}

(iii) Diagram

The specific labels will depend on your textbook.

They are often as follows.

a. Electron flow

b. Voltmeter or lightbulb

c. Electron flow

d. Cathode or Cu

e. Cu²⁺(aq) and NO₃⁻(aq)

f. Salt bridge

g. Zn²⁺(aq) and NO₃⁻(aq)

h. Anode or Zn

The salt bridge enables ions to flow in the internal circuit and to maintain electrical neutrality in the two compartments.

It often consists of a saturated solution of KCl.

As Zn²⁺ ions form in the anode compartment, Cl⁻ ions move in to provide partners for them.

As Cu²⁺ ions are removed from the cathode compartment, K⁺ ions move in to replace them.

User Heinrich Filter
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