Sour taste of lemon
a) The pH of distilled water is zero.
b) The higher the concentration of hydrogen ion, the higher the value of pH.
c) The pH of a hydrochloric acid solution is higher than that of the aqueous solution of sodium hydroxide.
d) The concentration of hydrogen ions in a solution with pH \(4\) is \(10\) times higher than that of a solution with pH \(5\).