HCl ----------> H(+) + Cl(-)
0,0045-x.........x...........x
0..................0,0045...0,0045
pH = -log[H+]
pH = -log[0,0045]
pH = 2,347
pOH = 14-pH
pOH = 14-2,347
pOH = 11,653
pOH = -log[OH-]
[OH-] = 10^-pOH
[OH-] = 10^-11,653
[OH-] = 2,2233·10^-12 mol/dm³
