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Question
The lattice site in a pure crystal cannot be occupied by ______.
Options
molecule
ion
electron
atom
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Solution
The lattice site in a pure crystal cannot be occupied by electron.
Explanation:
Pure crystals have constituents i.e., atoms or molecules or ions as lattice points which are arranged in fixed stoichiometric ratio. Electron can occupy the lattice site only when there is imperfection in solid and not in a pure crystal.
Hence, existence of free electrons are not possible, it is possible on in case of imperfection in solid.
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