General Chemistry
Behavioral Sciences
Lab Techniques

Acid-Base Properties

Now that we’ve explored the fundamental definitions of acids and bases, it’s time to delve into their properties. Beyond their classifications, acids and bases exhibit a wide range of characteristics, and one of the most pivotal aspects is their strength. Let’s shift our focus to understanding the varying degrees of acidity and alkalinity.

The strength of an acid or base refers to its degree of ionization in water. Strong acids and bases completely ionize upon dissolving. This means that strong acids will donate all their protons (H⁺) to water, while strong bases will accept all available protons. In contrast, weak acids and bases only partially ionize in water, leaving a significant portion of the molecules undissociated.

In terms of conductivity, strong acids and bases, due to their complete ionization, produce more ions and therefore conduct electricity more effectively than their weak counterparts.

While it is unlikely that the MCAT will straight up ask you to identify a strong acid or base it is important to memorize the 6 strong acids and the 6 strong bases as you may need that information to solve a more complicated problem.

They are as follows:

Strong Acids:

  1. Hydrochloric acid (HCl)
  2. Hydrobromic acid (HBr)
  3. Hydroiodic acid (HI)
  4. Nitric acid (HNO₃)
  5. Sulfuric acid (H₂SO₄)
  6. Perchloric acid (HClO₄)

Strong Bases:

  1. Lithium hydroxide (LiOH)
  2. Sodium hydroxide (NaOH)
  3. Potassium hydroxide (KOH)
  4. Calcium hydroxide (Ca(OH)2)
  5. Strontium hydroxide (Sr(OH)2)
  6. Barium hydroxide (Ba(OH)₂)

Keep in mind that all other acids outside of these 6 will be considered weak so by knowing the strong acids and bases you technically know which ones are weak as well. Even still the MCAT tends to consistently ask about several weak acids and bases that are worth knowing.

Weak Acids:

  1. Carboxcylic acids (R-COOH)
  2. Carbonic acid (H2CO3)

Weak Bases:

  1. Ammonia (NH3)