which has the lowest boiling point at 1 atm pressure

The element that has the lowest boiling point at 1 atmosphere (1 atm) pressure, often called the normal boiling point, is **Helium**. Its boiling point is approximately -268.9 degrees Celsius (4.22 Kelvin). This exceptionally low temperature is due to Helium being a noble gas. It possesses only extremely weak intermolecular forces, known as London dispersion forces, which means minimal energy is required to break these attractions and transition it from a liquid to a gas under standard atmospheric pressure.