In chemistry pH is a scale used to specify how acidic or basic a water based solution is Acidic solutions have a lower pH while basic solutions have a higher pH At room temperature 77 F pure water is neither acidic nor basic and has a pH of 7 A room temperature solution with a pH greater than 7 is basic while a room temperature solution with pH less than 7 is acidic The pH of a solution is given by mol L Hint log where H is the concentration of hydrogen ions in the solution measured in moles per liter mol L Use this formula to address the following items The pH of beer is 4 What is the hydrogen ion concentration of beer ph mol L H The pH of bread is 5 5 What is the hydrogen ion concentration of bread H log log H One can use the propties of logarithms to prove why