Question

What substances conduct electricity by the movement of ions?

Answer 1

To solve this question we first need to know what does it mean to electricity. Now a substance through which sound, heat, or electricity can flow is known as a conductor. Hence it can be said that an electrical conductor conducts electricity.

Complete answer:
Now, the ability of a substance to conduct electricity is known as conductance and is dependent on the conductivity of that substance.
Now, various materials conduct electricity like plasmas, semiconductors, superconductors, electrolytes, metals, and some nonmetals like conductive polymers and graphite.
Now, electrolytes conduct electricity by the movement of ions. This is because, when a compound is dissolved in an aqueous solution, it dissociates into ions. These dissolved ions move and flow throughout the solution and hence conduct electricity.
If the compound dissociates almost completely into ions in the aqueous solutions, it forms a strong electrolyte. These form strong acids and bases.
On the other hand, if a compound dissociates in a small quantity into ions in the aqueous solutions, it forms a weak electrolyte. These form weak acids and bases.
Since almost all ionic compounds dissociate completely in an aqueous solution, they form strong electrolytes.

Additional Information:
Metals conduct electricity due to the movement of free electrons inside the metals. Similarly, electricity is conducted by impurities containing semiconductors at room temperature and graphite.
Conducting polymers conduct electricity when they are doped by the addition or removal of electrons. Upon doping, the pi-bond electrons jump around the molecule and this movement of electrons in the polymer chain allows it to conduct electricity.

Note:
It should be noted that ionic compounds which exist in the solid state also conduct electricity by the movement of ions through its defects in the crystal lattice from one site to another.