system
Given the following post, respond as if you're commenting on Reddit:
human
Why doesn't wet stuff burn well?

I understand why pouring water directly on fire puts it out... but why can we put fire directly on a wet log and the water keeps it from burning?
gpt
The combustion reaction requires oxygen to happen. Water blocks it from happening and seeps into pores of the wood that would be stimulating the fire. The water needs to evaporate away for the wood to be combustible.