Use the following information to answer numerical$-$response question $5$ and question $12.$

Several metals are used in the manufacture of permanent magnets. A student wanted to compare the relative strengths of some of these metals and their corresponding ions as oxidizing and reducing agents. He immersed a strip of each metal in an aqueous solution of a metallic ion and recorded the following observations.

Selected Observations

$C{o}^{2+}(aq)+Nd(s)Co(s)+N{d}^{2+}(aq)$

$Y^{3+}(aq)+Nd(s)no$ evidence $of$ reaction

$S{m}^{2+}(aq)+Y(s)no$ evidence $of$ reaction

Chemical Species

$\backslash$table$[[1,Co(s),5,C{o}^{2+}(aq)$