About candle wax....

[macnpat]

Did you know that Candle wax totally evaporates? That is how some candles can be burned in a container without dousing the wick.

Dripless candles have harder exteriors which do not burn as easily as the innter portion.

Just thought you'd like to know.

[Jack]

But where does it go? It can't just disappear. Does it go to candle-wax heaven? The candle-wax afterlife? Does it come back as ear wax?

You've really made me curious now.

[Nathan Struth]

I thought it melts. I always remember wax dripping on things. Hanukah wasn't too fun when the wax hit the table.

[macnpat]

Wax eventually evaporates if it continues to burn.

[PatrickHenry]

Quote by: macnpat Wax eventually evaporates if it continues to burn.

Pat, I don't think so. It melts to a liquid that then gasifies at the ignition source which is the tip of the wick. I suppose that gasification immediately prior to combustion qualifies as "evaporation" but not in the classical sense of evaporating into the atmosphere...

[The Bacon Guy]

If we assume that wax is a mixture of hydrocarbons, it would burn in a similar way to other hydrocarbons, that is, the vapour burning, rather than the solid or liquid. Lighting the wick (which is itself usually coated in wax) would melt then evaporate the wax, the gaseous form of which could then burn. So strictly speaking, the wax does all evaporate, even if it does combust immediately after doing so.

If it simply evaporated into the air, the reaction would be endothermic and you wouldn't get any heat or light. Also, you'd end up with candle wax condensing on your window panes.

[gallo]

Quote by: macnpat Did you know that Candle wax totally evaporates? That is how some candles can be burned in a container without dousing the wick.

As has already been pointed out by PH and Bacon, you aren't exactly correct. I guess it depends on what you mean by "evaporates." The cotton wick, when lit begins to melt the wax below which then runs up the wick, where it is evaporated. Most of it them burns, yielding mostly carbon dioxide and water. However, lots of it doesn't burn. Just hold something at the apex of a candle flame and watch how black it gets. That is unburned carbon from the candle - although, I guess, to be exact it did evaporate.

Quote by: macnpat Dripless candles have harder exteriors which do not burn as easily as the innter portion.

True.

Quote by: macnpat Just thought you'd like to know.

Thanks, but I already knew that.

[macnpat]

Quote by: gallo Thanks, but I already knew that.

Well, thanks for sharing that info with the rest of us.

[Jern_Sandyer]

Quote by: The Bacon Guy If it simply evaporated into the air, the reaction would be endothermic and you wouldn't get any heat or light. Also, you'd end up with candle wax condensing on your window panes.

OK my science side is coming out right now and I just have to say that evaporation is not an endothermic REACTION. In is just a physical change and in order for a reaction to occur a substance has to change chemical composition such as in combustion.

(Don't worry I know what you meant I just did that for the Chemistry illiterate people out there. It is in some ways endothermic but not a reaction)

[macnpat]

Clearly, wax evaporates into a flammable gas. How anyone on this thread can dispute that, demonstrates the misunderstanding of the properties of gas and the dynamics of evaporation.

hehe

[Nono]

Off topic: Anyway, pat, you're better off these days debating the fate of candle wax than defending Boy George's "liberation" of Iraq, eh?

[gr8fuldaniel]

Quote by: Nono Off topic: Anyway, pat, you're better off these days debating the fate of candle wax than defending Boy George's "liberation" of Iraq, eh?

even more off-topic:


Boy George
I say we give him a shot........he could hardly do worse!


Edit to add:
On topic: I guess everyone knows NOTHING disappears. It only changes its' molecular structure. Some of its former self is changed to energy, some back to another form of mass. Some become unexplicable matter (as evidenced by above picture.)

[The Bacon Guy]

Quote by: gallo However, lots of it doesn't burn. Just hold something at the apex of a candle flame and watch how black it gets. That is unburned carbon from the candle

Technically, the carbon forming on the object held at the apex is not unburned. Since it is carbon and not the original substance (i.e. wax), it must be a product of combustion, albeit incomplete combustion.

Quote by: gallo That is unburned carbon from the candle - although, I guess, to be exact it did evaporate.

Again technically speaking, carbon cannot evaporate, since evaporation is the transition from liquid to gas. Carbon usually goes from solid grapahite straight to free gaseous atoms. In other words, it sublimes. Furthermore, I don't think the cabon formed on incomplete combustion even sublimes. If you think of smoke, it is not gaseous carbon, but rather suspended solid carbon.

Apologies for the excessive nitpicking by the way.

Quote by: Jern OK my science side is coming out right now and I just have to say that evaporation is not an endothermic REACTION. In is just a physical change and in order for a reaction to occur a substance has to change chemical composition such as in combustion

Damn, you got me. I suppose a decrease in the entropy of the surroundings would be a more appropriate description of what is going on. The decrease in entropy would of course mean that the system (i.e the candle) would be absorbing energy, rather than emitting it as heat and light.

Ok, I think between you, gallo and myself, we have cracked the mystery of wax combustion.

[macnpat]

Quote by: Nono Off topic: Anyway, pat, you're better off these days debating the fate of candle wax than defending Boy George's "liberation" of Iraq, eh?

How astute of you. Did the fact that this is the Science and Technology forum give me away?

[Jakob]

A 14 post debate about candle evaporation? Beautiful.

[Jack]

Now you know what makes this place so special.
Maybe I should say "special", like

When I was a boy of ten I had a very best friend Fred was kind with good intent But just a little different OH! Special Fred His momma dropped him on his head Now he's not so bright instead He's just a little bit special Just a little bit ... We'd play tag and he'd get hurt I'd play soldier, He'd eat dirt I liked math and spelling bee's Fred liked talking to a tree! OH! Special Fred His momma dropped him on his head Now she keeps him the shed 'Cause he's a little bit special Just a little bit... I ran track, hung out in malls Fred ran head first into walls I had girls and lots of clothes Fred had names for all his toes Oh! Special Fred His momma dropped him on his head Now he thinks he's a piece of bread 'Cause he's a little bit special Just a little bit... One day talkin' to Special Fred He grabbed a brick and he swung at my head And as he laughed at me that's when I knew That special Fred just made me special tooooo! Now I laugh as I count bugs I give strangers great big hugs Next to me Fred is fine Yeah, he's a fucking Einstien OH! Special Fred, and me Got knocked right in the head, you see Now we're not so bright instead We're a little bit special Just a little bit special That bastard friend made me special Just a little bit special...

"Special Fred"...Steven Lynch

[Nono]

Quote by: macnpat This is the Science and Technology forum.

Probably the safest place to be.

[macnpat]

Quote by: Nono Probably the safest place to be.

And oh, how I agree!!!!

I was looking for some really hot debate about candles. :rolleyes:

[Kamehameha34]

What.. you mean wax doesn't turn into styrofoam packing peanuts?! :(

[macnpat]

Quote by: Kamehameha34 What.. you mean wax doesn't turn into styrofoam packing peanuts?! :(

styrofoam packing peanuts........yummmmmmm....... wait.....

styrofoam? :eek: It'd take a hell of alotta coke to wash that down.:)