Sodium bisulfate, also known as sodium hydrogen sulfate is the sodium salt of the bisulfate anion, with the molecular formula NaHSO4. It is an acid salt, formed by the partial neutralization of sulfuric acid with an equivalent of sodium, usually sodium chloride or sodium hydroxide.
- NaHSO4 + NaCl → Na2SO4 + HCl
Sodium bisulfate is an acid salt. Heating (and even just sitting) can release sulfuric acid vapors, from small amounts to large quantities of fumes.
Sodium bisulfate is a white dry granular product. The anhydrous form is hygroscopic. Solutions of sodium bisulfate are acidic, 1M solution having a pH of < 1.
Sodium bisulfate is available as a pH lowering chemical for swimming pools.
Sodium bisulfate is made by mixing stoichiometric quantities of sodium hydroxide or sodium chloride and sulfuric acid.
- NaOH + H2SO4 → NaHSO4 + H2O
- NaCl + H2SO4 → NaHSO4 + HCl
- Make hydrochloric acid
- Make nitric acid (it will give off mostly nitrogen dioxide fumes if you use an alkali nitrate)
- Esterification catalyst 
- Chrome ion extraction from stainless steel 
Sodium sulfate will irritate the skin, eyes and mucous tissues on contact. Despite being a salt rather than a fully saturated acid, sodium bisulfate solutions have a much lower pH than many acids themselves, and should be treated with care. Prolonged exposure will damage the tissues. Do not attempt to smell sodium bisulfate. It is common for a sample to release sulfuric acid vapors, and these can build up in a container.
Sodium bisulfate should be stored in closed plastic or glass bottles.
Sodium bisulfate is not very dangerous to the environment, though it should be neutralized first before disposal.
- ↑ http://www.sciencemadness.org/talk/viewthread.php?tid=18767
- ↑ https://www.youtube.com/watch?v=TtPiwbRA4N8
- ↑ http://www.tandfonline.com/doi/abs/10.1080/00397919908085911?journalCode=lsyc20
- ↑ https://www.youtube.com/watch?v=hRGJn7x3Qyw
- ↑ http://www.sciencelab.com/msds.php?msdsId=9927267
- ↑ "The Volatile Chemist's" personal experience