Skip to Content
You searched for
Genre Advertisements Remove constraint Genre: Advertisements Place California--Pasadena Remove constraint Place: California--Pasadena Format Text Remove constraint Format: Text Rights No Copyright - United States Remove constraint Rights: No Copyright - United States

Search Constraints

Search Results

    • Bulletin No. 17
    • 1935 – 1940

    Arnold Beckman invented his first pH meter in 1934 at the request of a chemist from the California citrus industry, who needed an accurate way to measure the acidity of his product. The resulting instrument kicked off…

    • 1935 – 1940

    The quinhydrone electrode in this instrument was an alternative to Beckman's glass electrode. Quinhydrone electrodes are not reliable at measuring a pH greater than 8, at measuring solutions with strong oxidizing or…