chlorine
an element that was used was chlorinethere are some others such as tear and mustard gas
chlorine
Chlorine, which was used as a poisonous gas in World War I.
It was chlorine. That's the only poisonous gas that is a pure element that was used in WWI.
Chlorine gas was used as a weapon during World War I. Salt is Sodium chloride.
The common poison gas of WWI was Mustard Gas, a combination of Sulfur and Chlorine (C4H8Cl2S).
The common poison gas of WWI was Mustard Gas, a combination of Sulfur and Chlorine (C4H8Cl2S).
nickel
It was chlorine.
It was chlorine.
argon
are you asking what element is used or how it is used? if you are asking what element is used it would be charcoal. Chlorine gas has been added to kill bacteria.