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Question
Give a reason why two different rare (inert) gases find application in advertisement signs and fluorescent bulbs.
Solution
- Neon – In neon sign advertisements A brilliant red glow is seen on the passage of an electric current through neon gas at low pressure. The colour can be changed by mixing mercury vapour and argon with neon.
- Xenon – In fluorescent bulbs flash bulbs and lasers. It emits intense white light in discharge tubes.
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