The benzaldehyde should be Titrated in order to determine its acidity.
"Organic-Syntheses"
Conant, James Bryant
A 2 per cent bleach solution, containing very little excess base, was diluted with distilled water and the various dilutions Titrated with thiosulphate after the addition of potassium iodide.
"Chlorination of Water"
Joseph Race
The acidity is determined by weighing 20 grams of flour into a flask, adding 200 cubic centimeters of distilled water, shaking vigorously, and leaving the flour in contact with the water for an hour; 50 cubic centimeters of the filtered solution are then Titrated with a tenth normal solution of potassium hydroxid.
"Human Foods and Their Nutritive Value"
Harry Snyder