Question

Three different electrolytic cells A, B and C are connected in separate circuits. Electrolytic cell A contains sodium chloride solution. When the circuit is completed a bulb in the circuit glows brightly. Electrolytic cell B contains acetic acid solution and in this case the bulb in the circuit glows dimly. The electrolytic cell C contains sugar solution and the bulb does not glow. Give a reason for each of these observations.

Answer 1

Electrolytic cell A contains sodium chloride solution, that is a strong electrolyte. Strong electrolytes dissociate completely and contain large amount of ions in them. Thus, they conduct large amount of electricity, making the bulb in the circuit glow brightly.
Electrolytic cell B contains acetic acid solution, that is a weak electrolyte. Weak electrolytes dissociate partially and contain fewer amounts of ions in them. Thus, they conduct small amount of electricity, making the bulb in the circuit glow dimly.
Electrolytic cell C contains sugar solution, that is a non-electrolyte. Non-electrolytes contain only molecules and lack ions. So, they do not ionise and cannot conduct electricity. Thus, the bulb in the circuit does not glow at all.