Which gas is used in advertising signs and glows when electrified?

Which gas is used in advertising signs and glows when electrified?

• A. Ammonium
• B. Neon
• C. Uranium
• D. DDT

Answer: (B)

Electric signs work by passing electricity through a sealed tube filled with a gas, which becomes excited and emits light as it returns to a lower energy state. Neon is especially suited for this because it produces a bright, distinctive red-orange glow that is highly visible in signs. The glow you see in these signs comes from neon atoms emitting light when energized. The other options don’t fit this purpose: ammonium isn’t a gas used for glowing signage, uranium is a radioactive element and not used for this lighting, and DDT is a pesticide, not a light-emitting gas.

Electric signs work by passing electricity through a sealed tube filled with a gas, which becomes excited and emits light as it returns to a lower energy state. Neon is especially suited for this because it produces a bright, distinctive red-orange glow that is highly visible in signs. The glow you see in these signs comes from neon atoms emitting light when energized. The other options don’t fit this purpose: ammonium isn’t a gas used for glowing signage, uranium is a radioactive element and not used for this lighting, and DDT is a pesticide, not a light-emitting gas.