An electrorefining cell is used to produce silver metal from ions

CHEMISTRY · Single correct · AP · Chemistry · Thermodynamics and Electrochemistry · Thermodynamics and Electrochemistry

Problem

An electrorefining cell is used to produce silver metal from

\text{Ag}^{+}

ions. The current is maintained at

1.5\,\text{A}

for the first

10.0\,\text{min}

, after which it is increased to

3.0\,\text{A}

. If the goal is to obtain exactly

4.00\,\text{g}

of silver, approximately how many additional minutes (beyond the initial

10.0\,\text{min}

) must the higher current be applied? (Atomic mass of Ag

= 107.9\,\text{g mol}^{-1}

) (a)

20\,\text{min}

(b)

15\,\text{min}

(c)

35\,\text{min}

(d)

7.5\,\text{min}