十二水合磷酸氢二钠（磷酸氢二钠）

性状：无色结晶。在干燥空气中易风化。密封于阴凉处保存。

技术条件
含量（Na2HPO4·12H2O）,%                                          ≥99.0

pH值（50g/L,25°C）                                                       9.1~9.4

                                   杂质最高含量（以%计）
澄清度试验                                                                      合格
水不溶物                                                                         0.005
氯化物（Cl）                                                                  0.001
硫酸盐（SO4）                                                              0.005                                      
总氮量（N）                                                                  0.002
砷（As）                                                                        0.0005
钾（K）                                                                         0.01
铁（Fe）                                                                        0.0005
重金属（以Pb计）                                                          0.0005