Question

In the compound $Y{Ba}_2{Cu}_3{O}_7$ which shows superconductivity, what is the oxidation state of $Cu$?
Assume that the rare earth element yttrium is in its usual +3 oxidation state.

• A. $+\frac{7}{3}$
• B. $-\frac{7}{3}$
• C. $\frac{5}{3}$
• D. $-\frac{5}{3}$

Answer 1

Answer: (A)

$+\frac{7}{3}$

Let oxidation state of $Cu=x$

So, in $\left(Y{Ba}_2{Cu}_3{O}_7\right)$,

$3+(2\times 2)+3x-14=0$

$\therefore x=+\frac{7}{3}$