Question

According to Bronsted Lowry concept the correct order of strength of bases follows the order (1) \(\mathrm{CH}_{3} \mathrm{COO}^{-}>\mathrm{OH}^{-}>\mathrm{Cl}^{-}\) (2) \(\mathrm{OH}^{-}>\mathrm{CH}_{3} \mathrm{COO}^{-}>\mathrm{Cl}^{-}\) (3) \(\mathrm{CH}_{3} \mathrm{COO}^{-}>\mathrm{Cl}^{-}>\mathrm{OH}^{-}\) (4) \(\mathrm{OH}^{-}>\mathrm{Cl}^{-}>\mathrm{CH}_{3} \mathrm{COO}^{-}\)

Short answer

Option (2): \(\text{OH}^{-} > \text{CH}_3\text{COO}^{-} > \text{Cl}^{-}\).

Step-by-step solution

Identify Bronsted-Lowry Bases

According to the Bronsted-Lowry concept, a base is a species that accepts a proton (H+). The given species are \(\text{CH}_3\text{COO}^{-}\), \(\text{OH}^{-}\), and \(\text{Cl}^{-}\).

Understand the Base Strength Concept

The strength of a base depends on its ability to accept a proton. Strong bases readily accept protons, while weaker bases do so less readily. For instance, \(\text{OH}^{-}\) is considered a strong base because it has a high tendency to accept a proton and form water (H₂O).

Arrange the Bases Based on Known Strengths

Among the given bases, \(\text{OH}^{-}\) is known to be very strong, \(\text{CH}_3\text{COO}^{-}\) (the acetate ion) is weaker, and \(\text{Cl}^{-}\) (the chloride ion) is the weakest. This means the correct order of base strength from strongest to weakest is: \(\text{OH}^{-} > \text{CH}_3\text{COO}^{-} > \text{Cl}^{-}\).

Select the Correct Option

Compare the given options to the determined order. The correct order \(\text{OH}^{-} > \text{CH}_3\text{COO}^{-} > \text{Cl}^{-}\) matches option (2).

Key concepts

Base strength

In the realm of chemistry, the strength of a base is a critical concept to understand. A base's strength is influenced by its ability to accept protons. The more readily a base can accept a proton, the stronger it is. For example, hydroxide ions \(\text{OH}^-\) are well-known for their strong base properties due to their high tendency to attract and accept protons. This high proton affinity is key for reactions involving bases.

Additionally, the acetate ion \(\text{CH}_3\text{COO}^-\) and the chloride ion \(\text{Cl}^-\) differ in base strength, with acetate being stronger than chloride. Understanding these differences helps chemists predict and explain reaction outcomes.

It's important to remember that stronger bases are more likely to accept protons quickly, making them vital in various chemical processes.

Proton acceptor

A fundamental idea in the Bronsted-Lowry theory is that a base is a proton acceptor. This means it gains a hydrogen ion (H^+) during a reaction. Bases are identified by their ability to accept these protons.

Let's take a closer look at \(\text{OH}^-\). When \(\text{OH}^-\) accepts a proton, it forms water (H₂O), indicating its role as a strong proton acceptor. In contrast, weaker bases like \(\text{Cl}^-\) are less likely to accept protons due to their lower affinity for them.

Knowing which substances can act as proton acceptors helps in understanding acid-base reactions and predicting the behavior of different compounds in solution.

Always remember, in any Bronsted-Lowry reaction, the base is the species that receives the proton.

Order of bases

Understanding the order of bases in terms of their strength is crucial for solving chemistry problems. When comparing bases, we look at their relative abilities to accept protons.

For instance, the hydroxide ion \(\text{OH}^-\) is known to be very strong due to its high proton affinity. On the other hand, the acetate ion \(\text{CH}_3\text{COO}^-\) is a moderate base, and the chloride ion \(\text{Cl}^-\) is relatively weak.

The correct order from strongest to weakest is:
- \(\text{OH}^-\)
- \(\text{CH}_3\text{COO}^-\)
- \(\text{Cl}^-\)
This order helps determine the behavior of these bases in various reactions. Recognizing this hierarchy allows you to predict which base will dominate in accepting protons when multiple bases are present.