Because as long as there is no oxygen, people will suffocate! This is the absolute answer.

So scientists will not discuss the problem of asphyxiating gas, because it is not a problem at all.

On the contrary, toxic gases include paper and the like.

Poisonous gas (also known as "poisonous gas" or "poisonous gas", formerly known as "poisonous gas" or "poisonous gas") is a kind of gaseous toxin, which is a general term for gases harmful to organisms. Generally speaking, it is a disease that attacks or damages the respiratory tract, causing suffocation or pulmonary hemorrhage. Inhalation of excessive toxic gas will suffocate or even kill you.

It has strong binding force with red blood cells, replaces oxygen, or destroys cytochrome c oxidase, which reduces the oxygen carrying capacity of red blood cells. The more toxic gases, the lower the oxygen carrying capacity of red blood cells, leading to the death of cells due to hypoxia, such as carbon monoxide, azide, hydrogen sulfide, hydrogen antimonide or hydrogen cyanide.

Strong activity, easy to burn trachea and cause bleeding, such as ozone and chlorine.

And water form acidic substances, which corrode trachea: sulfur dioxide, sulfur trioxide, hydrogen fluoride, hydrogen chloride, etc.

There are two kinds of toxic gases: natural gas and artificial gas. Among them, poisonous gas artificially manufactured by chemical means is generally used for military purposes and belongs to chemical weapons.

Natural gas editor

carbon monoxide

nitric oxide

hydrogen sulfide

sulphur dioxide

chlorine

ozone

Fluorine gas

Artificial gas editor

carbonyl chloride

hydrocyanic acid

mustard gas

diphosgene

Lewis gas

VX (nerve agent)

Sarin (isopropyl methyl fluorophosphate)

Orange agent (commonly known as defoliant)