学过化学,做过化学实验的人,都知道有区别酸或碱的指示剂(Indicator)。这种指示剂中之最普通的是石蕋质(Litmus),用石蕋质区别酸性或碱性虽很方便,但不能告诉我们酸性或碱性的强弱。除石蕋质外,酸碱指示剂之比较常用的还有甲基橙(Methyl orange)和酚酞试液(Phenolph-thalein)等,也都是利用颜色的变化,但因变色比较灵敏,且能比较正确的指示出氢游子浓度即pH值,所以在滴定法(Titration)中常采用之。关于 People who have studied chemistry and have done chemical experiments know that there is an indicator that distinguishes acids or bases. The most common type of indicator is Litmus, which distinguishes acid or alkaline with stone, but does not tell us the strength of acidity or alkalinity. In addition to stone quality, the more commonly used acid-base indicator methyl orange (Methyl orange) and phenolphthalein test solution (Phenolph-thalein), also use the color change, but because of the more sensitive to color change, and can More accurate indication of the concentration of hydroponics that pH, it is often used in titration (Titration). on