I only need help with question 7.45, this is a Physical Chemistry question from

Question

I only need help with question 7.45, this is a Physical Chemistry question from Physical Chemistry (Silbey, Bawerti, Abendi) (4th edition).

I know that the answer is

(a) 2AgCl + Zn = 2 Ag + ZnCl2 (0.555 mol kg-1)

(b) - 195.9 KJ mol-1

(c) -77.6 J K-1 mol-1

(d) -219.0 KJ mol-1

I need help working the problems and learning how to approach them.

obtained from electromotive force measurements at constant temperature 7.45 (a) Write the reaction that occurs when the cell Zn | ZnCl2(0.555 mol kg)1 AgCI | Ag delivers current and calculate (b) 4,G, (c) ,s, and (d) ,A at 25 for this reaction. At 25°C, E 1.015 V and (a Ela7)P = -402 × 10-4 V K-1 7.46 The electromotive force of the cell Cd | CdCl2 -24H2O, sat. solution | AgCI | Ag at 25 is 0.675 33 V, and the temperature coefficient is 6.5 ×

Explanation / Answer

a)

The cell reaction is:

Zn(s) + 2AgCl(s) -------> ZnCl2 (aq.) + Ag(s)

b) rG = -nFE

n = 2

F = 96485 C/mol

E = 1.015 V

rG = -nFE = -2 x 96485 C/mol x 1.015 V = -195.9 kJ/mol

rG = -195.9 kJ/mol

c) rS = nF(dE/dT)p

n = 2

F = 96485 C/mol

(dE/dT)p = -4.02x10-4 VK-1

rS = nF(dE/dT)p = 2 X 96485 C/mol x (-4.02x10-4 VK-1) = 77.57 JK-1 mol

rS = 77.57 JK-1 mol

d) rH = -nF(E-TdE/dT)p

n = 2

F = 96485 C/mol

(dE/dT)p = -4.02x10-4 VK-1

rH = -nF(E-TdE/dT)p = - 2 x 96485 C/mol x (1.015 - (298 K x (-4.02x10-4 VK-1))

rH = -219.0 KJ mol-1

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