Where did the pH scale come from?

Nearly 110 years ago, while running experiments with beer at the world-renowned Carlsberg research lab in Copenhagen, Danish chemist Søren Peter Lauritz Sørensen developed the simple yet enduring pH scale, which measures whether a substance is acidic or basic.

What is pH mathematically defined as?

pH: A measure of the acidity or alkalinity of a fluid. Mathematically, the pH is the logarithm (to the base 10) of the reciprocal of the hydrogen ion concentration, [H+]. The pH is approximately equal to the negative logarithm of the H+ ion concentration expressed in molarity.

What is the formula of finding pH?

To calculate the pH of an aqueous solution you need to know the concentration of the hydronium ion in moles per liter (molarity). The pH is then calculated using the expression: pH = – log [H3O+].

How pH scale is established?

More precisely, pH is the negative of the base 10 logarithm of the activity of the H+ ion. At 25 °C, solutions with a pH less than 7 are acidic, and solutions with a pH greater than 7 are basic. The pH scale is traceable to a set of standard solutions whose pH is established by international agreement.

How do you find H+ from molarity?

The concentration can be converted to pH . Take a sample of nitric acid HNO3 with a molarity of 0.0032 M . The molarity becomes the [H+] concentration of 3.2×10−3 . We know this is the [H+] concentration because HNO3 is a strong acid, since the acid will completely dissociate into H+ and NO−3 .

What is the pH of H+?

In the case of a neutral solution, [H+]=10-7 , which we call a pH of 7. This means, for example, that a hydrogen-ion concentration of a solution with a pH of 4 is 10-4mol/l, meaning it contains 0.0001 mol of hydrogen ions in a solution of 1 liter.

What is pH in terms of log?

Answer: A neutral pH value is 7. A value less than 7 is acidic, while a value greater than 7 is basic. The formula for pH is pH = -log[H+]. This means pH is the negative base 10 logarithm (“log” on a calculator) of the hydrogen ion concentration of a solution.

What does pH measure in chemistry?

pH is a measure of how acidic/basic water is. The range goes from 0 to 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.