Ads
related to: ph meter for laboratory use of alcohol effects
Search results
Results From The WOW.Com Content Network
The Radiometer Corporation of Denmark was founded in 1935, and began marketing a pH meter for medical use around 1936, but "the development of automatic pH-meters for industrial purposes was neglected. Instead American instrument makers successfully developed industrial pH-meters with a wide variety of applications, such as in breweries, paper ...
In and of themselves, pH indicators are usually weak acids or weak bases. The general reaction scheme of acidic pH indicators in aqueous solutions can be formulated as: HInd (aq) + H 2 O (l) ⇌ H 3 O + (aq) + Ind − (aq) where, "HInd" is the acidic form and "Ind −" is the conjugate base of the indicator. Vice versa for basic pH indicators ...
H + does not cross through the glass membrane of the pH electrode, it is the Na + which crosses and leads to a change in free energy. When an ion diffuses from a region of activity to another region of activity, there is a free energy change and this is what the pH meter actually measures.
Arnold Orville Beckman (April 10, 1900 – May 18, 2004) was an American chemist, inventor, investor, and philanthropist. While a professor at California Institute of Technology, he founded Beckman Instruments based on his 1934 invention of the pH meter, a device for measuring acidity (and alkalinity), later considered to have "revolutionized the study of chemistry and biology". [1]
Therefore, pH values on the different scales cannot be compared directly because of differences in the solvated proton ions, such as lyonium ions, which require an insolvent scale that involves the transfer activity coefficient of hydronium/lyonium ion. pH is an example of an acidity function, but others can be defined.
pH meter: pH (chemical acidity/basicity of a solution) photometer: illuminance or irradiance planometer: area polarimeter: rotation of polarized light potentiometer: voltage (term is also used to refer to a variable resistor) profilometer: surface roughness protractor: angle psychrometer: humidity pycnometer: fluid density pyranometer: solar ...