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磷化锌的检验系根据下述原理: Zn_3p_2+3H_2SO_4→3ZnSO_4+2PH_3↑ 5PH_3+8KMnO_4+12H_2SO_4→4K_2SO_4+8MnSO_4+5H_3PO_4+12H_2O 2KMnO_4+5H_2C_2O_4+3H_2SO_4→2MnSO_4+K_2SO_4+10CO_2↑+8H_2O 根据反应式得出: 1ml 0.5N KMnO_4相当于8.065mg Zn_3P_2 称取磷化锌样品250mg放入250ml锥形瓶中,准确加入KMnO_4溶液(0.5N)35ml,硫酸(1+1)10ml,煮沸3分钟,用等浓度的草酸溶液(0.5N)滴至红色消失为止,再用KMnO_4溶液(0.5N)回滴至出现微
The test of zinc phosphide is based on the following principle: Zn_3p_2 + 3H_2SO_4 → 3ZnSO_4 + 2PH_3 ↑ 5PH_3 + 8KMnO_4 + 12H_2SO_4 → 4K_2SO_4 + 8MnSO_4 + 5H_3PO_4 + 12H_2O 2KMnO_4 + 5H_2C_2O_4 + 3H_2SO_4 → 2MnSO_4 + K_2SO_4 + 10CO_2 ↑ + 8H_2O According to the reaction equation Out: 1ml 0.5N KMnO_4 is equivalent to 8.065mg Zn_3P_2 Weigh 250mg zinc phosphide sample into a 250ml conical flask, accurately add KMnO_4 solution (0.5N) 35ml, sulfuric acid (1 + 1) 10ml, boil 3 minutes, and so on Concentration of oxalic acid solution (0.5N) until the disappearance of red, then KMnO_4 solution (0.5N) back to the emergence of micro