Classify each acid as strong or weak. If the acid is weak, write an expression for the acid ionization constant (K_a). c. HBr

Key Concepts

Strong vs. Weak Acids

Strong acids completely dissociate in water, releasing all their protons (H+), while weak acids only partially dissociate. This distinction is crucial for understanding acid behavior in solution, as strong acids have a high concentration of H+ ions, leading to a lower pH, whereas weak acids have a higher pH due to their incomplete dissociation.

Acid Ionization Constant (Ka)

The acid ionization constant (Ka) quantifies the strength of a weak acid by measuring the extent of its dissociation in water. It is defined by the equilibrium expression: Ka = [H+][A-]/[HA], where [H+] is the concentration of hydrogen ions, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the undissociated acid. A larger Ka value indicates a stronger weak acid.

Hydrobromic Acid (HBr)

Hydrobromic acid (HBr) is classified as a strong acid because it completely dissociates in aqueous solution. This means that when HBr is dissolved in water, it releases all of its hydrogen ions, resulting in a high concentration of H+ ions and a low pH. Understanding this classification helps in predicting the behavior of HBr in chemical reactions and its impact on pH.