The element chlorine exists at standard temperature and pressure as a green gas.
Iron Oxide Chlorine (Cl) is a green gas.
Its Cholrine.
Boron is the element that gives a green flame when burned. Boron compounds, such as boric acid or borax, are often used to create green-colored flames in fireworks.
Magnesium
"chlor" means green. the gas is green, thus the name.
hydrogen If the person posting the question is looking for a gas that is an element perhaps the answer they are looking for is Chlorine [Not that Hydrogen is not an element but I do not recall it having colour]
Every element has its own temperature of sublimation.
Chlorine . The name comes the Classical Greek for Green , Chloros. We also have the word ' chlorphyll' for a green organic chemical .
The element symbol Cl stands for chlorine. It is classified as a halogen gas and is poisonous to humans. At room temperature, it looks like a yellw-green gas.
You think probable to chlorine.
The elements in the center section are called transition elements.
Fluorine is a gas at room temperature and pressure. It is a highly reactive and corrosive element with a distinct yellow-green color.