# Thread: Reaching out for a little help

1. ## Reaching out for a little help

This is not for HW this is for the SW vs. ST tread. I am trying to find the heat of vaporization for Silicon dioxide (most common component in sand/dirt). If anyone has a book lying around to find it, it would be much appreciated.

2. If your wondering I am trying to calculate the amount of energy necessary to vaporize a small mountain. :-)

3. Seriously I went home and blew through my chem text books last night and found nothing!!!! Not in google, not wiki, not bing, not the mineralogy database, not in any MSDS sheets.

Maybe the data does not exist (hasn't been relevant to any tests?) I see people give figures in yahoo answers for it (usually different numbers in each post LOL) but I cannot find one reliable source.

I would assume that it's somewhat close to glass but idk.

4. 2230C is the boiling point according to Wikipedia

5. Originally Posted by Steve100
2230C is the boiling point according to Wikipedia
Thanks for trying! Unfortunately I need the figure which is related to the amount of energy required to vaporize the substance vs. how much of it you have. This is usually called the heat of vaporization or the enthalpy of vaporization and it is usually in units of joules/(temp*amount)

6. 359 kJ/mol to vaporise according to Wikipedia.

7. Originally Posted by Steve100
359 kJ/mol to vaporise again according to Wikipedia
That's for pure silicon, I need it for Silicon dioxide (sand/dirt/most of the earths crust essentially) but thanks again for trying!!!

8. Sorry, I was tired.

9. Try looking at Infomation from nuke testing. I'm sure I herd something about the attole that the French tested on turned to glass

10. The boiling point is 2230C, according to CRC Handbook, Ed 52
Molar Heat of vaporization is : 86900 (If i tracked along the right row.)
that is in cal/g-mol

11. Originally Posted by Believe
This is not for HW this is for the SW vs. ST tread. I am trying to find the heat of vaporization for Silicon dioxide (most common component in sand/dirt). If anyone has a book lying around to find it, it would be much appreciated.
Clear Fused Silica has a Specific Heat Capacity of 45.3 J/(mol.k).

Seems to be the closest available, should at least give you a ball park figure anyway.

12. Originally Posted by Trippy
Clear Fused Silica has a Specific Heat Capacity of 45.3 J/(mol.k).

Seems to be the closest available, should at least give you a ball park figure anyway.
See I had come across that before but I wasn't sure if it would be a proper approximation or not. Since I have at least a semi-consensous (of one other person lol) I suppose I can use that value now. Thank you very much for the help :-)

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