Question: adding 1/4 teaspoon of 10% phosphoric acid to 19 litres of water, what will be the pH? Let's go through the calculations step by step. Step 1. Convert mass ( or volume) of 10% phosphoric acid to mole per litre ( mol/L) The above calculation shows that 1/4 tsp of H3PO4 acid is 6.97e-5 mol/L Step 2. Input this value to BATE (or other app) to calculate pH The answer: pH = 4.16, ie too acidic !? If you use pipette instead of teaspoon, 1 drop = 0.05ml. So 1/4 TSP means roughly 25 drops If you actually aim for pH 5.6 (which is optimum pH for mashing), conc will be 2.51 e-6, or 1/100 tsp , 0.044 ml, roughly 1 drop Let's roll back a bit. From recipes of BarleyWine , summer rye , hefe Gordon Strong suggested to use 1/4 teaspoon of 10% phosphoric acid, which is targeting pH of 5.5..... Discussion on homebrewtalk forum. However using online BF water calc , Sparge pH would be 4.6. but he also added 1 tsp of CaCl2. 2H20. Mash pH change from 5.7 t...
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