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Redox Reactions — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryRedox Reactions2 Marks
Question
Assign oxidation number to the underlined elements in the following species:$\text{Na}\text{B}\text{H}_4$
✓

Answer

$\begin{matrix} +1&\text{x}&-1\\\text{Na}&\text{ B}&\ \text{ H}_4\end{matrix}$Then, we have
1(+1) + 1(x) + 4(-1) = 0
⇒ 1 + x - 4 = 0
⇒ x = +3
Hence, the oxidation number of B is +3.

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