A steady current of 1.00 ampere is passed through an electrolytic cell containin

Question

A steady current of 1.00 ampere is passed through an electrolytic cell containing a 1 molar solution of AgNO_3 and having a silver anode and a platinum cathode until 1.54 grams of silver is deposited. How long does the current flow to obtain this deposit? What weight of chromium would be deposited in a second cell containing 1-molar chromium (IIl) nitrate and having a chromium anode and a platinum cathode by the same current in the same time as was used in the silver cell? If both electrodes were platinum in this second cell, what volume of O_2 gas measured at standard temperature and pressure would be released at the anode while the chromium is being deposited at the cathode? The current and the time are the same as in

Explanation / Answer

a) faradays first law

w = zit

w= weight of substance deposited = 1.54 grams

t = time = ? sec

i = current = 1 amp

Z = E/F

E = equivalent weight of Ag = 107.9 equiv

F = faradays constant = 96500 c

1.54 = (107.9/96500)*1*t

t = time = 1377.3 sec

b)

faradays first law

w = zit

w= weight of substance deposited = ? grams

t = time = 1377.3 sec

i = current = 1 amp

Z = E/F

E = equivalent weight of Cr = 52/3 = 17.33 equiv

F = faradays constant = 96500 c

w = (17.3/96500)*1*1377.3

w = 0.247 grams

c)

    w1/w2 = E1/E2

   (0.247/X) = (17.33/8)

X = W2 = mass of O2 liberated = 0.114 grams

standard condition : P = 1 atm , T = 273.15 K

volume of O2 gas = nRT/P = (0.114/32)*0.0821*273.15/1

    =0.08 L

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.