How many elements in the periodic table are gases? Provide their positions in the periodic table.

(N/A) There are $11$ elements that exist as gases under standard conditions ($273.15 \ K$ and $1 \ bar$ pressure).
These elements are:
$1$. Hydrogen $(H)$: Group $1$,Period $1$
$2$. Nitrogen $(N)$: Group $15$,Period $2$
$3$. Oxygen $(O)$: Group $16$,Period $2$
$4$. Fluorine $(F)$: Group $17$,Period $2$
$5$. Chlorine $(Cl)$: Group $17$,Period $3$
$6$. Helium $(He)$: Group $18$,Period $1$
$7$. Neon $(Ne)$: Group $18$,Period $2$
$8$. Argon $(Ar)$: Group $18$,Period $3$
$9$. Krypton $(Kr)$: Group $18$,Period $4$
$10$. Xenon $(Xe)$: Group $18$,Period $5$
$11$. Radon $(Rn)$: Group $18$,Period $6$