universal indicator & pH paper

They are not the same. As it stated, pH paper is a paper. pH papers are made of paper impregnated with pH indicators or mixtures of indicators. Universal Indicator is a pH indicator that transitions through numbers 3-12 (on the pH chart) to indicate the acidity and alkaline of solutions. Although there are a number of commercially available universal pH indicators, most are a variation of a formula patented by Yamada in 1923.

2 樣野當然唔同la

universal indicator 係一種液體
本身係綠色gea
但當佢在acid condition下會變成 黃色/ 橙色
在alkali condition下會變成 藍色/ 紫色

而pH paper係一張 paper
當在acid condition 的時候會變紅色
alkali condition會變藍色
其實係每個唔同gea pH value 佢都會變成唔同gea 顏色
買pH paper 的時候會有一張野寫明咩顏色係咩pH
老師會有, 上網都可以找到