Relationship With The Neutral Point of Water
Water molecules dissociate into equal amounts of H3O+ and OH−, so their concentrations are equal to 1.00 × 10−7 mol∙dm−3 at 25 °C. A solution in which the H3O+ and OH− concentrations equal each other is considered a neutral solution. In general, the pH of the neutral point is numerically equal to pKw/2.
Pure water is neutral, but most water samples contain impurities. If an impurity is an acid or base this will affect the concentrations of hydronium ion and hydoxide ion. Water samples which are exposed to air will absorb the acid carbon dioxide and the concentration of H3O+ will increase. The concentration of OH− will decrease in such a way that the product remains constant for fixed temperature and pressure.
Read more about this topic: Self-ionization Of Water
Famous quotes containing the words relationship, neutral, point and/or water:
“We must introduce a new balance in the relationship between the individual and the government—a balance that favors greater individual freedom and self-reliance.”
—Gerald R. Ford (b. 1913)
“The seashore is a sort of neutral ground, a most advantageous point from which to contemplate this world. It is even a trivial place. The waves forever rolling to the land are too far-traveled and untamable to be familiar. Creeping along the endless beach amid the sun-squall and the foam, it occurs to us that we, too, are the product of sea-slime.”
—Henry David Thoreau (1817–1862)
“Those who have mastered etiquette, who are entirely, impeccably right, would seem to arrive at a point of exquisite dullness.”
—Dorothy Parker (1893–1967)
“Milton says, that the lyric poet may drink wine and live generously, but the epic poet, he who shall sing of the gods, and their descent unto men, must drink water out of a wooden bowl. For poetry is not “Devil’s wine,” but God’s wine.”
—Ralph Waldo Emerson (1803–1882)