Question

Solid NaCl is a bad conductor of electricity because
A. In solid $$NaCl$$, there are no ions
B. In solid$$NaCl$$, ions cannot move freely
C. In solid$$NaCl$$, there are no electrons
D. None of the above.

Answer 1

Hint: In solid$$NaCl$$, ions are bound by strong electrostatic forces. Free ions participate in good electric conduction. When $$NaCl$$ is dissolved in water, ions are capable of moving and conducting electricity.

Complete step by step answer:
Solid $$NaCl$$ is a bad conductor of electricity because the charged particles (ions) in solid $$NaCl$$ are not capable of moving as they are bound by strong electrostatic forces. As a result, they can not conduct electricity. However, water ions are capable of moving when $$NaCl$$ is dissolved in it and hence conduct electricity.
Now we consider the given options to find the correct answer:
In solid$$NaCl$$, there are no ions – this statement is wrong because solid NaCl has charged particles i.e ions namely $$Na+$$and $Cl-$.
In solid$$NaCl$$, ions cannot move freely – this statement is true because the charged particles (ions) in solid $$NaCl$$ are not capable of moving as they are bound by strong electrostatic forces. As a result, they can not conduct electricity. So solid$$NaCl$$ is a bad conductor.
In solid $$NaCl$$, there are no electrons – this statement is wrong because $$NaCl$$ has electron that is $C{l}^{-}$
We get the right option from the given options.

So, the correct answer is “Option B”.

Note:
As solid $$NaCl$$ is a bad conductor, solid $$KCl$$ is also not a good conductor. Solid $$KCl$$ is a crystalline solid and the potassium and chlorine atoms are ionically bonded within a crystalline matrix that prevents them from easily moving.
When $$NaCl$$ is dissolved in water ions $$N{a}^{+}$$ and $C{l}^{-}$ are capable of moving. They become free in the molten state. Hence they can conduct electricity.