CHM 131 Lecture 8: CHEM 131 one class 8

• School: University of Rochester
• Department: Chemistry
• Course: CHM 131
• Professor: Benjamin Hafensteiner

Document Summary

An acidic solution has a high concentration of hydrogen ions (h+) greater than that of pure water. A basic solution has a low h+ concentration, less than that of pure water. Autoionization of water: h2o (l) h+ (aq) + oh- (aq) Hydrogen ions are spontaneously generated in pure water by the dissociation (ionization) of a small percentage of water molecules. Acidic solutions have a higher h+ concentration than water, while basic (alkaline) solutions have a lower h+ concentration. Typically, the hydrogen ion concentration of a solution is expressed in ph. ph is calculated as the negative log of a solution"s hydrogen ion concentration. An acid is a substance that increases the concentration of hydrogen ions in a solution, usually by donating one of its hydrogen atoms through dissociation. A base, in contrast, raises ph by providing hydroxide or another ion or molecule that scoops up hydrogen ions and removes them from solution.