Introduction, Acid-Base Equilibria | Chemistry 2e

Learning objectives

Brønsted-Lowry Acids and Bases
pH and pOH
Relative Strengths of Acids and Bases
Hydrolysis of Salt Solutions
Polyprotic Acids
Buffers
Acid-Base Titrations

View original figure (external; image not reproduced in this text edition)

Original figure description: A photograph is shown of a pond formed in a sinkhole. Layers of limestone with trees and shrubs surround the murky green water of the pond.

Sinkholes such as this are the result of reactions between acidic groundwaters and basic rock formations, like limestone. (credit: modification of work by Emil Kehnel)

Liquid water is essential to life on our planet, and chemistry involving the characteristic ions of water, H⁺ and OH^–, is widely encountered in nature and society. As introduced in another chapter of this text, acid-base chemistry involves the transfer of hydrogen ions from donors (acids) to acceptors (bases). These H+ transfer reactions are reversible, and the equilibria established by acid-base systems are essential aspects of phenomena ranging from sinkhole formation (CNX_Chem_14_00_Sinkhole) to oxygen transport in the human body. This chapter will further explore acid-base chemistry with an emphasis on the equilibrium aspects of this important reaction class.

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