QQuestion
The electronic configuration of an element is 2,8,2. The hydroxide of this element can produce …………… hydroxyl ions per molecule.
(a) 3
(b) 2
(c) 1
(d) 0
✓Answer
(b) 2
Explanation –
An element with electronic configuration 2, 8, 2 is magnesium (Mg) with valency 2. Its hydroxide is Mg(OH)2, which contains 2 hydroxyl (OH−) ions per molecule.
\mathrm{Mg(OH)_2} \rightarrow \mathrm{Mg^{2+}} + 2\mathrm{OH^-}Related Questions
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