Physics

Physics, 07.04.2020 21:27, ellie55991

A galvanic cell based on these half-reactions is set up under standard conditions where each solutions is 1.00 L and each electrode weighs exactly 100.0 g. How much will the Cd electrode weigh when the non-standard potential of the cell is 0.03305 V?

answer

Answers: 2

Show answers

Answers

Answer

answered: robert7248

Complete Question

$Fe^{2+} + 2e^----- Fe \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ E^0_{red} = - 0.441 V$

$Cd^{2+} + 2e^- ----- Cd \ \ \ \ \ \ \ \ \ \ \ \ \ \ E^0_{red} = -0.403V$

A galvanic cell based on these half-reactions is set up under standard conditions where each solutions is 1.00 L and each electrode weighs exactly 100.0 g. How much will the Cd electrode weigh when the non-standard potential of the cell is 0.03305 V?

The mass is M= 117.37g

Explanation:

The overall reaction is as follows

$Cd^{2+} + Fe Fe^{2+} + Cd$

The reaction is this way because the potential of $Cd^{2+} \ reducing \ to \ Cd$ is higher than the potential of $Fe^{2+} \ reducing \ to \ Fe$ so the the Fe would be oxidized and $Cd^{2+}$ would be reduced

At equilibrium the rate constant of the reaction is

$Q = \frac{concentration \ of \ product }{concentration \ of reactant }$

$= \frac{[Fe^{2+}[Cd]]}{[Cd^{2+}][Fe]}$

The Voltage of the cell $E_{cell} = E_{Cd^{2+}/Cd } + E_{Fe^{2+} /Fe}$

Substituting the given values into the equation

$E_{cell} = -0.403 -(-0.441)$

= 0.038V

The voltage of the cell at any point can be calculated using the equation

$E = E_{cell} - \frac{0.059}{n_e} Q$

Where $n_e \ is \ the \ number\ of\ electron$

Substituting for Q

$E = E_{cell} - \frac{0.059}{n_e} \frac{[Fe^{2+}[Cd]]}{[Cd^{2+}][Fe]}$

When E = 0.03305 V

$E = E_{cell} - \frac{0.59}{n_e} \frac{Fe^{2+}}{Cd^{2+}}$

Since we are considering the Cd electrode the equation becomes

$E= E_{cell} - \frac{0.059}{n_e} [\frac{1}{Cd^{2+}} ]$

Substituting values and making [ $Cd^{2+}$ ] the subject

$[Cd^{2+}] =\frac{1}{e^{[\frac{0.03305- 0.038}{\frac{0.059 }{2} }] }}$

= 0.8455M

Given from the question that the volume is 1 Liter

The number of mole = concentration * volume

= 0.8455 * 1

= 0.8455 moles

At the standard state the concentration of $Cd^{2+}$ is =1 mole /L

Hence the amount deposited on the Cd electrode would be

= Original amount - The calculated amount

= 1 - 0.8455

= 0.1545 moles

The mass deposited is mathematically represented as

$mass = mole * molar \ mass$

The Molar mass of Cd = 112.41 g/mol

Mass = 0.1545 *112.41

= 17.37g

Hence the total mass of the electrode is = standard mass + calculated mass

M= 100+ 17.37

M= 117.37g

Answer

answered: Jasten

The mass of Cd is 121.92 g

Explanation:

The initial concentrations are:

$nFe=\frac{mass}{molecular weight} =\frac{100}{55.845} =1.7906\\nCd=\frac{100}{112.411} =0.88959$

Initially:

[Fe2+] = 1.7906[Cd2+] = 0.88959

After the reaction:

[Fe2+] = 1.7906 + x

[Cd2+] = 0.88959 - x

Eo = Ered - Eoxidation = (-0.403 - 0.441) = 0.038

The Nernst equation is:

$E=0.038-\frac{0.0592}{2} log\frac{[Fe^{2+}] }{[Cd^{2+}] } \\0.03305=0.038-0.0296log\frac{1.7906+x}{0.88959-x}$

Solving for x:

x = -0.195

[Fe2+] = 1.7906 -0.195 = 1.5956

[Cd2+] = 0.88959 + 0.066 = 1.08459

Mass of Cd2+ = 1.08459 * 112.411 = 121.92 g

Answer

answered: Guest

Efficiency is an act of doing something

Answer

answered: Guest

Kiloleter, mega leterhope this !

Other questions on the subject: Physics

Physics, 22.06.2019 13:00, Ryleetarver

Discuss how the hardness or softness of the landing surface is related to the time required to stop the egg

Answers: 1

Physics, 22.06.2019 13:00, livvyr0cks

Ways that industry and agriculture use physical properties to separate substances

Answers: 1

Physics, 22.06.2019 17:00, Janae2918

Using proper grammar, spelling, and punctuation, write at least one 5 sentence paragraph describing 3 ways we use the elements of the electromagnetic spectrum (ems) in our everyday lives.

Answers: 2

Physics, 22.06.2019 18:30, bubblzthechicken

Asmall grinding wheel has a moment of inertia of 4.0×10−5 kg⋅m2 . what net torque must be applied to the wheel for its angular acceleration to be 150 rad/s2 ?

Answers: 3

Do you know the correct answer?

A galvanic cell based on these half-reactions is set up under standard conditions where each solutio...

Questions in other subjects:

Konu

History, 10.04.2020 06:17

May 28, 1830 Chapter CXLVIII An Act to provide for an exchange of lands with the Indians residing in any of the states or territories, and for their removal...

Konu

Mathematics, 10.04.2020 06:17

The graph of f(x) = 2x is shown on the grid. On a coordinate plane, an exponential function approaches y = 0 in quadrant 2 and increases into quadrant 1. It goes throug...

Konu

Mathematics, 10.04.2020 06:17

Four clowns practiced juggling bowling pins yesterday. The table below shows the number of bowling pins that each clown dropped and the number of minutes that each clown juggled.

Konu

Mathematics, 10.04.2020 06:17

How would the image be different if point A were closer to the triangle?...

Konu

Social Studies, 10.04.2020 06:17

Personally Responsible? Actively Participates? Addresses the Root of the Problem? The hook

Konu

History, 10.04.2020 06:17

Read the excerpt from "How I Learned English." Someone said "shin" again, There was a wild stamping of hands on the ground, A kicking of feet, and the fit O...

Konu

Mathematics, 10.04.2020 06:17

F(x) = x2 – 3x-2 is shifted 4 units left. The result is g(x). What is g(x)?...

Konu

English, 10.04.2020 06:17

How many years did it take to build the Great Pyramid?...

Konu

History, 10.04.2020 06:17

After the allies take Africa what happens to Mussolini...

Konu

English, 10.04.2020 06:17

*20 points* PART A: Which of the following identifies a theme of the text? a) Homes provide physical and emotional security for families. b) While change can be f...

Other tasks in the category: Physics More task