Why does (fire)wood burn better when split?

[Redneck in training]

Here is little more of the physics:
Thre is a relationship between dimension, surface area and volume.
Volume is proportional to dimension cubed while surface area is proportional to dimesion square. So as the dimesion gets smaller surface are dereases at much lower rate than volume.
It implies that finely split one pound of wood has much greater area than single peace one pound of wood. As above responses already pointed out greater surface area results in greater reaction speed (hotter fire) etc.

 

[jymbee]

... As above responses already pointed out greater surface area results in greater reaction speed (hotter fire) etc.

Or to look at it another way, which would burn faster: a single piece of wood five inches in diameter, or that same piece of wood split into a pile of chopsticks?

 

[IndyIan]

Or to look at it another way, which would burn faster: a single piece of wood five inches in diameter, or that same piece of wood split into a pile of chopsticks?

If you can control the air flow for the chopsticks you'll get more heat energy and a cleaner burn out of them though... I've got an EPA indoor stove with a window and if I get a hot hot bed of coals, you can throw in a single sheet of paper and then close the air intake and it will burn for much longer than you'd think.

 

[jymbee]

If you can control the air flow for the chopsticks you'll get more heat energy and a cleaner burn out of them though...

Very true. That's why one of the best examples of an inefficient heating device is the average home fireplace. As I'm sure most know, one of the main reasons fireplaces are ill suited for much beyond their pleasant ambiance (and actually have a negative heating effect) is that there's little way to control air flow.