MCQ
The compound $YB{a_2}C{u_3}{O_7}$ which shows superconductivity has copper in oxidation state ........ Assume that the rare earth element Yttrium is in its usual $ + \,3$ oxidation state
- A$3/7$
- ✓$7/3$
- C$3$
- D$7$
$3 + 2 \times 2 + 3x - (2 \times 7) = 0$
$3 + 4 + 3x - 14 = $$3x = 7$
$x = \frac{7}{3}$.
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