Google Doodle celebrates the founder of the pH scale, SPL Sorensen, with an animated game involving sorting acidic and alkaline substances

Google Doodle today involves going back to your chemistry lessons from school. The Doodle celebrates SPL Sørensen, a Danish biochemist, who is credited with having founded the pH scale system which is a scale for measuring the acidity and alkalinity. [caption id=“attachment_4486183” align=“alignleft” width=“380”] SPL Sorensen. Image: Wikipedia[/caption] Born on 9 January 1868 in Havrebjerg in Denmark, Søren Peder Lauritz Sørensen worked at the Carlsberg Laboratory in Copenhagen from 1901 to 1938. The concept of pH values was introduced in 1909 as a convenient way to express acidity. According to Science History, the context for introducing the concept of pH was moving away from colour change tests for indicating the degree of acidity and alkalinity to electrical methods of deriving it. In the electric method, “the current generated in an electrochemical cell by ions migrating to oppositely charged electrodes was measured, using a highly sensitive (and delicate) galvanometer.” That was until Sorensen developed the pH scale which easily expressed the hydrogen ion concentration. The doodle comprises a simple animated game, which shows you a food item or other substances, and you have to sort it according to its pH values. Now a pH scale measures how acidic or alkaline a substance is and it goes from values 0-14. If the pH scale is less than 7, the the substance is acidic, if it’s more than 7 then the substance is alkaline. A pH value of 7 means the substance is neutral. Generally water has a pH value of 7 as it’s neither acidic nor alkaline. [caption id=“attachment_4486181” align=“alignnone” width=“1280”] Google Doodle pH scale game[/caption] So in the doodle, you are presented with a tomato, egg, broccoli, lemon, a soapy solution, battery and you have to click on either arrows which will sort them on either side of the pH scale. A correct guess will sort the substance and will also show the pH value of the said substance. If you are wrong, the laboratory scientist, modeled on Sorensen, will wildly shake his head asking you to try again. After sorting the six substances, they all animate again and make the Google logo. At the time of writing, it isn’t clear why this particular Doodle is on the Google home page today, as 29 May does not coincide with either Sorensen’s birth or death, which is generally the practice of having doodles behind certain personalities. The Doodle’s reach is around India, the whole of North America, parts of South America, parts of Europe, South East Asia, Australia and New Zealand.