Do the alchemist's fire bombs surpass the Resist Energy (fire) spell?
Thx.
Resist energy (fire) applies to any sort of fire damage, whether magical or natural.
The subject gains resist energy 10 against the energy type chosen, meaning that each time the creature is subjected to such damage (whether from a natural or magical source), that damage is reduced by 10 points before being applied to the creature's hit points.
Short answer: No.
It's worth getting a second energy type for your bombs as soon as possible if you're playing an alchemist, for exactly this reason. Coming up against enemies with energy resistance or a immunity to fire is not uncommon.
If you're defending against an Alchemist then Resist Energy: Fire is a good start, but chances are pretty goid they'll have a backup energy type. Prepping a second (maybe even third) instance of Resist Energy is a good idea.