The metal filament in a light bulb is hot enough to glow. The bulb is filled with argon instead of air.
Which is the best explanation for using argon?
Argon is non-flammable, so the gas inside the bulb cannot catch fire when the filament glows
Argon has a low density, so it rises away from the filament and stops it from overheating
Argon atoms have eight outer electrons, so the gas conducts heat away from the filament
Argon is inert, so the hot filament does not react with it as it would with oxygen in air
44 exam-style questions on Edexcel GCSE Chemistry 7.3 Group 0, covering 7.3.1 The noble gases. Each one has a worked solution and a mark scheme showing where the marks go.