Question:
Lowest oxidation number of an atom in a compound \( A_2B \) is -2. The number of electrons in its valence shell is:
Lowest oxidation number of an atom in a compound \( A_2B \) is -2. The number of electrons in its valence shell is:
Updated On: Jul 12, 2025
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Correct Answer: 6
Solution and Explanation
A2B → 2A+ + B2−, B2− has a complete octet in its di-anionic form, thus in its atomic state it has 6 electrons in its valence shell. As it has a negative charge, it has acquired two electrons to complete its octet.
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