Liquid drain cleaner, 4 gallons. Use two with sodium nitrate to synthesize nitric acid after it's been distilled. Chemistry shit is cheap enough and not really suspicious. Distill all four gallons for your sulfuric, use half for your nitric. Phenol is real cheap, especially in liquid solutions of ~20%.
what does that make
Trinitrophenol, also known as picric acid. It's not very sensitive, and easily made. Can still be set off when dry, which is why you mix in some water to make it a paste. Also, don't heat it up too much.