Question
Assign oxidation number to the underlined elements in the following species:
H4P2O7
✓
Answer
$\begin{matrix} +1&\text{x}&-2\\\text{H}_4&\text{ P}_2&\ \text{ O}_7\end{matrix}$
Then, we have
4(+1) + 2(x) + 7(-2) = 0
⇒ 4 + 2x - 14 = 0
⇒ 2x = +10
⇒ x = +5
Hence, the oxidation number of P is +5.
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