Identifying the Non-Conjugate Acid-Base Pair Among the Given Options
Which of the following is not a conjugate acid-base pair?
Understanding conjugate acid-base pairs is crucial in the field of chemistry, particularly in the study of acid-base reactions. A conjugate acid-base pair consists of two substances that differ by a single proton (H+). The acid in the pair donates a proton, while the base accepts it. This concept is fundamental to understanding the behavior of substances in various chemical reactions. However, identifying which substances form a conjugate acid-base pair can sometimes be challenging. In this article, we will explore some examples and determine which of the following is not a conjugate acid-base pair.
In the first example, we have hydrochloric acid (HCl) and chloride ion (Cl-). HCl is a strong acid, meaning it readily donates a proton. When it loses a proton, it forms its conjugate base, Cl-. Therefore, HCl and Cl- are a conjugate acid-base pair.
Next, let’s consider carbonic acid (H2CO3) and bicarbonate ion (HCO3-). Carbonic acid is a weak acid, and when it loses a proton, it forms bicarbonate ion, which acts as a base. Hence, H2CO3 and HCO3- are a conjugate acid-base pair.
Moving on to the third example, we have ammonia (NH3) and ammonium ion (NH4+). Ammonia is a weak base, and when it accepts a proton, it forms ammonium ion, which acts as an acid. Therefore, NH3 and NH4+ are a conjugate acid-base pair.
Finally, let’s examine the last example: water (H2O) and hydroxide ion (OH-). Water can act as both an acid and a base. When it donates a proton, it forms the hydroxide ion, which acts as a base. Conversely, when it accepts a proton, it forms the hydronium ion (H3O+), which acts as an acid. Thus, H2O and OH- are not a conjugate acid-base pair because they are the same substance in different states (protonated and deprotonated).
In conclusion, the correct answer to the question “Which of the following is not a conjugate acid-base pair?” is water (H2O) and hydroxide ion (OH-). It is important to understand the concept of conjugate acid-base pairs in chemistry, as it helps explain the behavior of substances in acid-base reactions and various other chemical processes.
