JEE Mains · Chemistry · STD 12 - p -Block elements - ll
Lowest Oxidation number of an atom in a compound \(\mathrm{A}_2 \mathrm{~B}\) is -\(2\) . The number of an electron in its valence shell is _______.
- A \(4\)
- B \(5\)
- C \(6\)
- D \(7\)
Answer & Solution
Correct Answer
(C) \(6\)
Step-by-step Solution
Detailed explanation
\(\mathrm{A}_2 \mathrm{~B} \rightarrow 2 \mathrm{~A}^{+}+\mathrm{B}^{-2}, \mathrm{~B}^{-2}\) has complete octet in its dianionic form, thus in its atomic state it has 6 electrons in its valence shell. As it has negative charge, it has acquired two electrons to complete its octet.
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