NaHSO4 Caution: irritating to eyes. Appropriate quantity as a replacement for chemistry set chemical. Image for illustration only, actual product may appear different.
Sodium bisulfate, also known as sodium hydrogen sulfate (NaHSO4), is an acid salt. It is a dry granular product that can be safely shipped and stored. The anhydrous form is hygroscopic. Solutions of sodium bisulfate are acidic, with a 1M solution having a pH of < 1.
Image & text from Wikipedia.