Acids and Bases

The general steps for identifying whether a common substance is a strong acid, a weak acid, a strong base, or a weak base are below.  

Step 1: Identify the substance as an Arrhenius acid or base using the following criteria.

  • The names of the acids end in “acid”. Acid formulas have one of these forms: HX(aq) or HaXbOc.

  • Ionic compounds that contain hydroxide
    (OH-) , carbonate (CO32-) , or hydrogen carbonate (HCO3-) anions are basic. Ammonia, NH3, is also a base.

Step 2: If the substance is an acid or base, determine whether it is strong or weak.

  • All common acids except HCl(aq), HNO3, and H2SO4 are weak.

  • All common bases except metal hydroxides are weak.