Which group name do the non-metals in group 18 have?

The elements of group 18 of the periodic table are known as noble gases or inert gases.

Explanation:

The noble gases are placed in group 18 of the periodic table.  These gases have a very low chemical reactivity, that is, little combination with other elements of the periodic table. For that reason they are called inert gases. This behavior is due to its electronic configuration, because its outermost layer or valence layer is always complete, being the stable element by itself, without the need to borrow or share electrons.

As mentioned, noble gases are not very reactive, that is, they do not usually form bonds between atoms. This means that they don't react much with other substances, they don't even react between atoms of the same gas.

In summary, the elements of group 18 are non-reactive elements.

Finally, the elements of group 18 of the periodic table are known as noble gases or inert gases.