Expert Answers
mwestwood eNotes educator| Certified Educator

Often uses to compare solution acidities such as in products for humans like hydogen peroxide; PH is a logrithmic measure of hydrogen ion concentration in aquaeous solutions.  It was originally defined by biochemist Soren Peter Lauritz Sorenson in 1909.

A measure of the degree of the acidity or the alkalinity of a solution is measured on a PH scale of 1 to 14 with the midpoint of 7.0 representing neutrality.  This is a measure of intensity, not capacity.  So, in a swimming pool, one desires a neutral score so that people will be comfortable in the water since too much acidity can burn the skin.

lit24 | Student

pH stands for potential of Hydrogen. It is the measure of the acidity or basicity of a solution.

It is defined as the logarithm of the reciprocal  of hydrogen-ion concentration in gram atoms per liter on  a scale from 0 to 14 of the acidity or alkalinity of a solution where 7 is neutral, and greater than 7 is more basic and less than 7 is more acidic.

The concept of pH was first introduced by the Danish chemist Soren Peder Lauritz Sorensen at the Carlsberg Laboratory in 1909.

talo09 | Student

The percentage of hydrogen ions

An acid is a substance that dissociates in water to release hydrogen ions.

An base is a substance theat accepts a hydrogen ion or donates.

acidic: 1-6

nuetral: 7

basic: 8-14

byersk | Student

It defines whether a substance is a base or an acid and the level of acidity or basity.

roy01 | Student

pH is a measure of the acidity or basicity of a solution. It is defined as the cologarithm of the activity of dissolved hydrogen ions (H+). ... Unit to measure the hydrogen-ion concentration. It is measured on a scale from 0 to 14 with 7 the neutral point.

The pH of a solution is a measure of the molar concentration of hydrogen ions in the solution and as such is a measure of the acidity or basicity of the solution. The letters pH stand for "power of hydrogen"