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 $Cl^- $
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 \[Na^+ \] and $Cl^- $ are capable of moving. They become free in the molten state. Hence they can conduct electricity.