Question

Helium is the lightest gas (com, pos)

Answer 1

Answer:

Helium (He), chemical element, inert gas of Group 18 (noble gases) of the periodic table. The second lightest element (only hydrogen is lighter), helium is a colourless, odourless, and tasteless gas that becomes liquid at −268.9 °C (−452 °F).

...

Helium.

Answer 2

Answer:

Helium is the lightest gas in the Earth's atmosphere. For this reason, nowadays, Helium balloons have replaced Hydrogen balloons, which were in use previously. Hydrogen is lighest than helium. Because hydrogen have a one proton and one electron.