Re: Sodium Hexametaphosphate tech grade Appearance: White power Specification: Total phosphate as P2O5: 68% min Inactive phosphate as P2O5 : 7.5% max Iron: 0.05% max PH value(1% solution) : 5.8-7.3 Water insoluble: 0.05% max Re: Sodium Hexametaphosphate food grade Appearance: White powder Specification: Total phosphate as P2O5: 68% min Inactive phosphate as P2O5 : 7.5% max Iron: 0.05% max PH value(1% solution) : 5.8-6.5 Water insoluble: 0.06% max Heavy metals as Pb: 0.001% max As: 0.0003% max F: 0.003% max