pH
PH (noun) means a scale from 0 to 14 measuring how acidic or alkaline a solution is, with 7 being neutral. Example: “The gardener tested the soil's pH before planting the blueberries.”
noun
1
A scale from 0 to 14 measuring how acidic or alkaline a solution is, with 7 being neutral.
"The gardener tested the soil's pH before planting the blueberries."
"Pure water has a pH of about 7."
How to use pH
Learner’s notesIn plain EnglishA number showing how acidic or basic something is — low pH is acidic, high pH is alkaline, 7 is neutral.
Common pairings
pH level
pH balance
test the pH
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Word forms
- Plural
- pHs
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The gardener tested the soil's _____ before planting the blueberries.
Etymology
Introduced in 1909 by chemist S. P. L. Sørensen; the "H" stands for hydrogen, and the "p" likely abbreviates a word for "power" or "potential" in Sørensen's notation.
Synonyms
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pH scale
Frequently asked questions
What does “pH” mean?
The word “pH” means a scale from 0 to 14 measuring how acidic or alkaline a solution is, with 7 being neutral. In plain terms, a number showing how acidic or basic something is — low pH is acidic, high pH is alkaline, 7 is neutral.
How do you use “pH” in a sentence?
Here is “pH” used in a sentence: “The gardener tested the soil's pH before planting the blueberries.”
What part of speech is “pH”?
“PH” is a noun.
Where does the word “pH” come from?
The word “pH” dates back to around 1909. Introduced in 1909 by chemist S. P. L. Sørensen; the "H" stands for hydrogen, and the "p" likely abbreviates a word for "power" or "potential" in Sørensen's notation.
Is “pH” a common word?
“PH” is a fairly common word in modern English, usually learned at around the B2 level.
Why is pH written with a lowercase p and a capital H?
By convention, pH is always written with a small "p" and a capital "H," even at the start of a sentence. The capital "H" refers to hydrogen, which is why it is not lowercased.
What is the difference between a high and a low pH?
A low pH (below 7) means a solution is acidic, while a high pH (above 7) means it is alkaline, or basic. A pH of exactly 7 is neutral, like pure water.
What is the difference between pH and acidity?
pH is the scale used to measure how acidic or alkaline a solution is, whereas acidity refers to the acidic quality itself. A lower pH value indicates greater acidity.
Can pH go above 14 or below 0?
The pH scale is usually described as running from 0 to 14, which covers the great majority of everyday solutions. Very strong acids or bases can technically fall slightly outside this range, but 0 to 14 is the standard reference.
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