Question

Why argon give red colour when electricity passed through it?

Answer 1

Violet to pale lavender blue is the colour emitted by argon and it never gives red colour

Answer 2

The Open University Argon is used as the inert atmosphere in many light bulbs – an electric current is passed through a wire to heat it up so that it gets so hot it emits light. At these temperatures the metal would react with any oxygen present which is why an inert gas is needed.