Can I make cemical salt by wall of salt?

[With a box]

What I wanted to do is...
1. cast wall of salt to create wall made of Ammonium Nitrate.
2. shatter it.
3. mix with oil(or suger, or anything that can give carbon).(this mixture calls ANFO (http://en.wikipedia.org/wiki/ANFO) eka: fertilizer bomb)
4. explode it with electric shock. (Electric Jolt (http://dndtools.pw/spells/spell-compendium--86/electric-jolt--3535/))

it will make few tons of explosive...

And yes, I killed a catgirl.

[eggynack]

There's no real indication that you have control over the type of salt created, no. So, if the salt you cited is the one produced, then it's the one produced by every casting regardless of intent, and if it's not, then that other salt, whether of a single variety or a mixture, is the one produced by every casting. And, y'know, I somehow doubt that the specific salt you brought up is the one created by the spell.

[Spore]

I would require an Craft (Alchemy) check for that. The rarer the material and the more exotic in comparison to the standard alchemical ingredients it is, the higher the DC. Also keep in mind that non-compressed salts actually more likely burn than explode making the squares deal fire damage (mundane fire, 1d6) rather than exploding.

Because your chemistry-savvy DM can retaliate with: "Wall of Salt also has no density given so it doesn't explode. It just burns down slowly." Personally I would still go for the standard definition of salt rather than introducing chemical compounds.

[Heikold]

Huh, I'd never considered this. Even table salt comes in sodium chloride and potassium chloride forms. "Wall of Salt" is like saying "Wall of Metal".

If I were the DM I'd use legal ruling: "Ambiguity in a contract always benefits the party that did not write it".

[BWR]

Make sure to add the clause "so long as it's not bleeding obvious what was intended." I'm quite confident that Wall of Salt was never meant to be harvested and sold for profit nor to be used for a bomb.