[A123]

Hello!

Can someone explain to me if Paraffin wax has a boiling point? I was looking for a substance with a melting range and boiling range in stead of a melting point and boiling point, so I though of a candle. I found that the melting range of paraffin wax is 47 - 65 C, but I cannot find a boiling range. The link below shows (like other sources) only an autoignition point (of 245C). Does this mean that liquid paraffin wax does not evaporate, and therefore doesn't have a boiling point/range? Or does it evaporate but does it reach the autoignition point before all the liquid could turn into gas?
(How does autoignition occur by the way, an reaction with oxigen?)

Thank you!

http://books.google.co.za/books?id=CxZ9AlbN_sQC&pg=PA373&lpg=PA373&dq=%22paraffin+wax%22+autoignition&source=bl&ots=obSXF3knXC&sig=909i9X14Jf-4MwBm7FrzGtoxTiE&hl=en&ei=CnvSTJvBPI7pObj9scIP&sa=X&oi=book_result&ct=result&resnum=3&ved=0CCEQ6AEwAg#v=onepage&q=%22paraffin%20wax%22%20autoignition&f=false

[A123]

Hi, can someone help me please?

I found out now that the vapor, that arises when the liquid paraffin wax is heated, is the thing that is getting on fire due to a combination of heat, oxygen and the'fuel' itself. But I still don't know if 245C is the first time this vapor appears, since I could not find a boiling point..

Also, say you have paraffin wax in a closed flask, would the flask explode when there is a fire in it (high pressure)? or would just all the paraffin wax vapor burn untill there is nothing left. (or when there is no more oxygen left, will the leftover liquid paraffin wax continue to evaporate)?

Thanks!

[dzoys]

i recall having a lab with paraffin wax and this is what i can definitely deduce from my prelab work, experiment, and post lab research.

1- paraffin wax does has a relatively low boiling point but it's uncertain b/c i believe it is a common name for any mixture that falls under the category. that is why you can't find one boiling point. if you think about it, no candle is the same anyways.

2- the low boiling point brings us to that ignition property u r referring to, which is also very low- a small flame can remain ignited and isolated for a long time because the melting, boiling, and ignition points should be relatively close together.

3- capping this in a closed system, the oxygen would run out and the flame would go out. pressure can't build up bc of the heat required to bring the substance from solid to vapor capable for ignition does not time well with the apparatus u r working with.

i can't even begin to think of a different scale. but i hear if u melt and seal water drops into the wax it will create some sort of display.(don't recommend)