Hamad stated that nitrogen gas is noncombustible so is water vapour. if both nitrogen and water are in gaseous state then why the term gas and vapour were used by hamad?

Unlike clouds, fog, or mist which are simply suspended particles of liquid water in the air, water vapour itself cannot be seen because it is in gaseous form. Water vapour in the atmosphere is often below its boiling point. When water is boiled the water evaporates much faster and makes steam.

Explanation:

Unlike clouds, fog, or mist which are simply suspended particles of liquid water in the air, water vapour itself cannot be seen because it is in gaseous form. Water vapour in the atmosphere is often below its boiling point. When water is boiled the water evaporates much faster and makes steam.

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a:

by the combination of an unlimited number of elements

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.