Water in contact with air is acidic, rather than neutral,
dueto dissovled carbon dioxide. Water in equilibrium with theair
contains 4.4 X 10 -5% CO2. Theresulting
carbonic acid, H2 CO3 , gives thesolution a
hydrogen ion concentration of 2.0 X10-6M , about 20
times larger than thatof pure water. Calculate the pH of the
solution.