At room temperature (about 25 °C and 1 atm), 11 elements are gases: hydrogen, nitrogen, oxygen, fluorine, chlorine, helium, neon, argon, krypton, xenon, and radon.

Quick Scoop: Gaseous Elements at Room Temperature

  • Total gaseous elements: 11.
  • They’re mostly on the upper right of the periodic table (noble gases and some nonmetals).
  • They include:
    • Hydrogen (H) – diatomic gas.
    • Nitrogen (N) – diatomic gas.
    • Oxygen (O) – diatomic gas.
    • Fluorine (F) – diatomic gas.
    • Chlorine (Cl) – diatomic gas.
    • Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), Radon (Rn) – monatomic noble gases.

Where They Sit on the Periodic Table

  • The noble gases (He, Ne, Ar, Kr, Xe, Rn) form the far-right column (Group 18).
  • The other gaseous elements (H, N, O, F, Cl) are nonmetals near the top-right side, with hydrogen typically shown at the top left but behaving like a light nonmetal gas.

Fast Facts (SEO-Friendly Highlights)

  • If you’re asking “how many elements are gaseous at room temperature?” → the answer is 11.
  • Only two elements are liquids at ordinary room temperature: mercury and bromine; everything else (besides the 11 gases) is solid.

Mini HTML Table (Gaseous Elements)

Here’s a simple HTML table listing them:

html

<table>
  <thead>
    <tr>
      <th>Element</th>
      <th>Symbol</th>
      <th>Type</th>
    </tr>
  </thead>
  <tbody>
    <tr><td>Hydrogen</td><td>H</td><td>Diatomic nonmetal gas</td></tr>
    <tr><td>Nitrogen</td><td>N</td><td>Diatomic nonmetal gas</td></tr>
    <tr><td>Oxygen</td><td>O</td><td>Diatomic nonmetal gas</td></tr>
    <tr><td>Fluorine</td><td>F</td><td>Diatomic halogen gas</td></tr>
    <tr><td>Chlorine</td><td>Cl</td><td>Diatomic halogen gas</td></tr>
    <tr><td>Helium</td><td>He</td><td>Monatomic noble gas</td></tr>
    <tr><td>Neon</td><td>Ne</td><td>Monatomic noble gas</td></tr>
    <tr><td>Argon</td><td>Ar</td><td>Monatomic noble gas</td></tr>
    <tr><td>Krypton</td><td>Kr</td><td>Monatomic noble gas</td></tr>
    <tr><td>Xenon</td><td>Xe</td><td>Monatomic noble gas</td></tr>
    <tr><td>Radon</td><td>Rn</td><td>Monatomic noble gas</td></tr>
  </tbody>
</table>

TL;DR: There are 11 elements that are gaseous at room temperature, and they cluster mainly in the upper-right region of the periodic table among the noble gases and light nonmetals.

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