Why is vapor visible?

[mnmlh]

I can't seem to get to the bottom of this with wikipedia, google or this site. Is there particulate matter in there, or are the vaporized compounds that we enjoy just taking on a "vapor state", which I always thought was just with H20?

 

[DevoTheStrange]

vapor is visible the same reason clouds are. The vapor refracts the light

 

[mnmlh]

All vapor? So, it's molecules and not particulates that are refracting light? I guess that makes sense.

 

[max]

Just keep in mind that vapor isn't nearly as visible as smoke, and when vaping, the 'tail end' vapor hits that aren't visible in less than great lighting, can be seen when exhaling into good light (especially streaming sunlight that shows floating dust particles). I've often exhaled a hit that I didn't feel, thinking the bowl is done, and have seen vapor when exhaled under lamp lighting. I think, in a lot of cases, that people are dumping a bowl that's not quite fully vaped. Another reason to save your ABV for eating, vaping at higher temps, whatever.

 

[Frickr]

Just keep in mind that vapor isn't nearly as visible as smoke, and when vaping, the 'tail end' vapor hits that aren't visible in less than great lighting, can be seen when exhaling into good light (especially streaming sunlight that shows floating dust particles). I've often exhaled a hit that I didn't feel, thinking the bowl is done, and have seen vapor when exhaled under lamp lighting. I think, in a lot of cases, that people are dumping a bowl that's not quite fully vaped. Another reason to save your ABV for eating, vaping at higher temps, whatever.

but what is fully vaped then max? i have sat and puffed on a single pd stem for 45 mins and blew out visable vapor under normal light. even after 5 hits i still have visable vapor in low light. i just give up on the tubes after a while just because i get stoned and dont need any more and am tired of puffing on the same tube. but the vapor never seems to end on some strains. now yes the vapor is far less thick then the initial few hits, but vapor is still being produced none-the-less.

 

[Hippie Dickie]

but the vapor never seems to end on some strains. now yes the vapor is far less thick then the initial few hits, but vapor is still being produced none-the-less.

i've experienced this too. i think there's no longer THC in the vapor -- no taste so i don't know what it is. maybe the trichome shell itself is being vaporized.

 

[mnmlh]

maybe the trichome shell itself is being vaporized.

Maybe the h20 in the oils is steaming off?

 

[luchiano]

but the vapor never seems to end on some strains. now yes the vapor is far less thick then the initial few hits, but vapor is still being produced none-the-less.

i've experienced this too. i think there's no longer THC in the vapor -- no taste so i don't know what it is. maybe the trichome shell itself is being vaporized.

Thc is an odorless and colorless substance so it probably is the thc still being vaporized. If the temperature is 385f or lower the first puff will be mostly essential oils(taste and smell) with a little cannabinoids in the vapor.

Check out this study:

http://www.ncbi.nlm.nih.gov/pubmed/19852551

Cannabis smoke condensate III: The cannabinoid content of vaporised Cannabis sativa.

Pomahacova B, Van der Kooy F, Verpoorte R.

Institute of Biology, Leiden University, The Netherlands.

Cannabis sativa is a well-known recreational drug and, as such, a controlled substance of which possession and use are illegal in most countries of the world. Due to the legal constraints on the possession and use of C. sativa, relatively little research on the medicinal qualities of this plant has been conducted. Interest in the medicinal uses of this plant has, however, increased in the last decades. The methods of administration for medicinal purposes are mainly through oral ingestion, smoking, and nowadays also inhalation through vaporization. During this study the commercially available Volcano vaporizing device was compared with cannabis cigarette smoke. The cannabis smoke and vapor (obtained at different temperatures) were quantitatively analyzed by high-performance liquid chromatography (HPLC). In addition, different quantities of cannabis material were also tested with the vaporizer. The cannabinoids:by-products ratio in the vapor obtained at 200 degrees C and 230 degrees C was significantly higher than in the cigarette smoke. The worst ratio of cannabinoids:by-products was obtained from the vaporized cannabis sample at 170 degrees C.


This site has a graph and is more in depth.
http://stash.norml.org/new-study-examines-cannabis-vaporization

 

[DevoTheStrange]

I think the h2o would be the first thing to go, it has a lower boiling temp than THC.

I've noticed in really harsh light that I can see vapor that I normally wouldn't see in normal lighting.
I also noticed in the same light that vapor was still coming out in my exhales for up to a minute after, although very light traces.

 

[The_Other_Shoe]

Well, just to put it in my perspective, you can see steam coming off a pot of boiling water yea? What is in steam? Besides that, when it's cold out and you breathe, you can see your breath, if you breathe out hotter air than what is surrounded, will you not have some sort of visible-ness? It doesn't necessarily have to be anything different from the air that you drew in. I could be totally wrong but that is my logic.

 

[mnmlh]

I do think water vapor is playing into it, but there is some good information in here. Thanks guys.

 

[AGBeer]

What are you saying? That vapor should be heard and not seen?

Vapor has feelings too ya know?

 

[Ash]

I've noticed the same thing, where I can seemingly puff a stem endlessly and still get 'vapor'. Could it be that when you pull hot dry air into the lungs, the hot air pulls moisture out of the lungs and that the vapor we're seeing when we exhale is actually our own lung juice?