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प्रश्न
The lattice site in a pure crystal cannot be occupied by ______.
विकल्प
molecule
ion
electron
atom
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उत्तर
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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