purchase of heavy chemical ( formaldihyde, scale softener, bleaching powder, caustic soda, washing soda, phosphoric acid, hcl ) . , purchase of heavy chemicals: , formaladehyde 35%, nhc / chemcon make , scale softener ( polychem, nhc, tata / modi / dcw / chemcon make ) , bleaching powder 33% available chlorine, tata / modi / shriram make , washing soda tata / modi / dcw make , phosphoric acid ( make – star / excel / ballarpur / gujrat alkali ) , h3p04 = 85%, p2o5 = 61.5, ph – 1.5 ( 0.1 nag-solution ) , sp. gravity – 1.68, quality – food grade. , caustic soda ( star / excel / gujrat alkali / ballarpur make ) purity :- naoh 95% by mass ( other specification as per isi ) , packing in 50 kg. hdpe bag ( net weight caustic soda 50 kg. ) , hydroceloric acid