1. caustic soda (sodium hydroxide) 2. flakes, pearls 3. soluble in water easily 4. ... , chemical fiber, pesticides, petro-chemical, medical and food industries. ItemsSuper GradeStandard grade.Sodium Hydroxide %≥99.599.0Sodium Carbonate%≤0.50.8Sodium Chloride %≤0 ... .060Copper %≤0.00020.0003Calcium %≤0.0050.008 hot sale NaOH 99% caustic soda flakes pearls