关于用K_2Cr_2O_7＋K_2CrO_4作双指示剂法示例的探讨

On Using K_2Cr_2O_7+K_2CrO_4 as Means of Double Indication

在酸碱滴定的双指示剂法示例中，用Ｋ２Ｃｒ２Ｏ７＋Ｋ２ＣｒＯ４取代Ｎａ２ＣＯ３＋ＮａＨＣＯ３，并改用溴甲酚绿和酚酞作指示剂．其结果表明，本法滴定的终点前颜色变化较明显，终点较敏锐，准确度较好．

in the use of double indication in acid and alkali titration, using K2CrO7 + K2CrO4.instead of Na2CO3 + NaHCO3, and bromocresol green and phenolphthalein as indicators,the result shows that final colours change evidently in the titration with sharp destination and good accuracy.