Citric acid is used to make bathbombs, it is the second greatest ingredient after bicarbonate of soda. You use the citric acid to create the fizzy reaction.
Our citric acid in anhydrous (without water) which creates a harder, smooth finish bath bomb.
When making bath bombs bicarbonate of soda is your main ingredients which you use 2 parts bicarb to 1 part citric or 3:1 with bicarb always being your main ingredient.
As well as being used to make bath bombs citric acid has so many other uses such as for household cleaning and degreasing/descaling. Seriously take a minute to google citric it has so many different uses!