酸碱度的PH中的P应大写还是小写

我的书上是P小写，但老师说随便

在化学的历史中，H都指代的是氢离子或氢离子浓度，这个没有问题
而p的写法稍有变化，在早期化学中，pH有各种写法，比如p[H](首创于丹麦科学家），也有H作p的下标的写法，在法语和德语中，pH也可翻译为氢离子的势能（potential hydrogen）
在现代化学中，小写p指代的是“以10为底数的对数值”，比如pH，pK等等。
所以我们目前用的pH，就是“氢离子浓度以10为底数的对数值”的意思（记得加上负号）

翻译自维基百科
The concept of p[H] was first introduced by the Danish chemist Søren Peder Lauritz Sørensen at the Carlsberg Laboratory in 1909[4] and revised to the modern pH in 1924 to accommodate definitions and measurements in terms of electrochemical cells. In the first papers, the notation had the "H" as a subscript to the lowercase "p", as so: pH.
The exact meaning of the "p" in "pH" is disputed, but according to the Carlsberg Foundation, pH stands for "power of hydrogen".[5] It has also been suggested that the "p" stands for the German Potenz (meaning "power"), others refer to French puissance (also meaning "power", based on the fact that the Carlsberg Laboratory was French-speaking). Another suggestion is that the "p" stands for the Latin terms pondus hydrogenii (quantity of hydrogen), potentia hydrogenii (capacity of hydrogen), or potential hydrogen. It is also suggested that Sørensen used the letters "p" and "q" (commonly paired letters in mathematics) simply to label the test solution (p) and the reference solution (q).[6] Currently in chemistry, the p stands for "decimal cologarithm of", and is also used in the term pKa, used for acid dissociation constants.

酸碱度应该是pH不写PH或Ph

p是小写的，H是大写的。不信的话把书拿来对照一下，都是宋体字！

考试的时候应小写（我是高一的）

你好！ PH是拉丁文“Pondus hydrogenii”一词的缩写 应该大写 仅代表个人观点，不喜勿喷，谢谢。

PH是拉丁文“Pondus hydrogenii”一词的缩写 应该大写