Explanation

• Carbon dioxide (CO₂) is used in fire extinguishers.
• It extinguishes fire by displacing oxygen and cooling the burning material.
• CO₂ fire extinguishers are especially effective for electrical and flammable liquid fires.
• Carbon dioxide is a colorless and non-flammable gas.
• It leaves no residue after use.

Last verified on 09-07-2026

Explanation

• Freezing Point: 0°C
• Fahrenheit: 32°F
• Kelvin: 273.15 K

Additional information:

• Boiling Point: 100°C (212°F or 373.15 K)
• Standard Atmospheric Pressure: 1 atm (760 mmHg)

Last verified on 06-07-2026

Explanation

• Symbol: Hg
• Atomic number: 80
• Melting point: -38.83 °C
• Atomic mass: 200.59 u

Last verified on 13-03-2026

Explanation

• Fluorescent lamps mainly use argon gas (often with a small amount of mercury vapor).
• Electric current excites the gas and produces ultraviolet (UV) light.
• The UV light then hits the phosphor coating inside the tube.
• This coating produces visible light.
• Argon helps in starting and maintaining the discharge.

Last verified on 14-06-2026

Explanation

• The usual gases used for lifting airships are hydrogen and helium.
• Hydrogen is the lightest known gas and thus has great lifting capacity,
• Helium is not as buoyant but is far safer than hydrogen because it does not burn.

Last verified on 01-04-2026