In Order to Determine the Identity of a Particular Lanthanide $\to$

question 15

Multiple Choice

In order to determine the identity of a particular lanthanide metal Sm,a voltaic cell is constructed at 25°C with the anode consisting of the lanthanide metal as the electrode immersed in a solution of 0.0819 M SmCl₃,and the cathode consisting of a copper electrode immersed in a 1.00 M Cu(NO₃) ₂ solution.The two half-reactions are as follows: Sm(s) $\to$ Sm³⁺(aq) + 3e^-
Cu²⁺(aq) + 2e^- $\to$ Cu(s)
The potential measured across the cell is 2.67 V.What is the identity of the metal?

• A)Ce
• B)Eu
• C)Dy
• D)Sm
• E)Gd