ph

¹ American  

Optics.

1. phot; phots.

---

pH ² American  

Chemistry.

1. the symbol for the logarithm of the reciprocal of hydrogen ion concentration in gram atoms per liter, used to express the acidity or alkalinity of a solution on a scale of 0 to 14, where less than 7 represents acidity, 7 neutrality, and more than 7 alkalinity.

---

Ph ³ American  

abbreviation

Chemistry.

1. phenyl.

---

ph. ⁴ American  

abbreviation

1. phase.

2. phone.

---

P.H. ⁵ American  

abbreviation

1. Public Health.

---

ph ¹ British  

abbreviation

1. Philippines

---

pH ² British  

noun

1. potential of hydrogen; a measure of the acidity or alkalinity of a solution equal to the common logarithm of the reciprocal of the concentration of hydrogen ions in moles per cubic decimetre of solution. Pure water has a pH of 7, acid solutions have a pH less than 7, and alkaline solutions a pH greater than 7

---

ph. ³ British  

abbreviation

1. phase

---

Ph ⁴ British  

symbol

1. phenyl group or radical

---

pH Scientific  

/ pē′āch′ /

1. A numerical measure of the acidity or alkalinity of a solution, usually measured on a scale of 0 to 14. Neutral solutions (such as pure water) have a pH of 7, acidic solutions have a pH lower than 7, and alkaline solutions have a pH higher than 7. The pH of lemon juice is 2.4; that of household ammonia is 11.5. The normal pH for human blood is 7.4.

2. ◆ The letters pH stand for potential of hydrogen, since pH is effectively a measure of the concentration of hydrogen ions (that is, protons) in a substance. The pH scale was devised in 1923 by Danish biochemist Søren Peter Lauritz Sørensen (1868–1969).

---

pH Cultural  

1. In chemistry, a measure of the strength of an acid or a base. A neutral solution has a pH of 7; acids a pH between 0 and 7; bases a pH from 7 to 14. Specially treated strips of paper (see litmus), or more precise instruments, may be used to measure pH.

---

Example Sentences

Money also allowed the organization to hire the smartest Ph.D.s and engineers.

From The Wall Street Journal

When mutations disrupt this channel, pH regulation is impaired.

From Science Daily

"When we started on the project around six years ago, it was assumed that TMEM175 was a potassium channel. Its function was completely unknown. We've now been able to demonstrate that TMEM175 not only conducts potassium ions, but also protons, and is thus directly involved in the regulation of pH -- that is, the proton concentration -- in the interior of lysosomes."

From Science Daily

These proteins also showed an unusual ability to remain stable under extreme conditions, including very high temperatures, extreme pH levels, and highly salty environments.

From Science Daily

By understanding how bacterial metabolism drives this type of motion, scientists may be able to slow or stop it by altering environmental conditions such as pH or sugar levels.

From Science Daily