* It's a gas at room temperature: Unlike metals, which are generally solids at room temperature, helium exists as a gas.
* It's a poor conductor of heat and electricity: Helium is a very poor conductor of heat and electricity, unlike most metals, which are good conductors.
* It has a low melting and boiling point: Helium has an extremely low melting and boiling point, further distinguishing it from metals, which generally have high melting points.
* It's not malleable or ductile: Helium cannot be hammered into sheets (malleable) or drawn into wires (ductile), as these are properties typically associated with metals.
* It forms no metallic bonds: Helium does not form metallic bonds, which are the characteristic bonds between metal atoms.
* It's located on the right side of the periodic table: Elements on the right side of the periodic table are generally nonmetals, while those on the left side are metals. Helium resides in Group 18, the noble gases, which are all nonmetals.
In summary, helium lacks the key properties that define metals and possesses the characteristics that define nonmetals. This is why it's classified as a nonmetal.
