Determine if each salt will form a solution that is acidic, basic, or pH-neutral. e. C₆H₅NH₃NO₂

Verified step by step guidance

1. Identify the ions that make up the salt \( \text{C}_6\text{H}_5\text{NH}_3\text{NO}_2 \). The salt dissociates into \( \text{C}_6\text{H}_5\text{NH}_3^+ \) (anilinium ion) and \( \text{NO}_2^- \) (nitrite ion).
2. Determine the nature of the cation \( \text{C}_6\text{H}_5\text{NH}_3^+ \). This is the conjugate acid of the weak base aniline (\( \text{C}_6\text{H}_5\text{NH}_2 \)), so it will tend to donate protons, making the solution more acidic.
3. Determine the nature of the anion \( \text{NO}_2^- \). This is the conjugate base of the weak acid nitrous acid (\( \text{HNO}_2 \)), so it will tend to accept protons, making the solution more basic.
4. Compare the strengths of the conjugate acid and base. Since both the cation and anion come from weak acids and bases, the pH of the solution will depend on the relative strengths of \( \text{C}_6\text{H}_5\text{NH}_3^+ \) as an acid and \( \text{NO}_2^- \) as a base.
5. Conclude the nature of the solution. If \( \text{C}_6\text{H}_5\text{NH}_3^+ \) is a stronger acid than \( \text{NO}_2^- \) is a base, the solution will be acidic. If \( \text{NO}_2^- \) is a stronger base than \( \text{C}_6\text{H}_5\text{NH}_3^+ \) is an acid, the solution will be basic.

Key Concepts

Salt Hydrolysis

Salt hydrolysis is the reaction of a salt with water to produce an acidic or basic solution. When a salt dissolves in water, its constituent ions can interact with water molecules, leading to the formation of either H+ or OH- ions, which determine the pH of the solution. Understanding this process is crucial for predicting whether a salt will yield an acidic, basic, or neutral solution.

Acidic and Basic Ions

Salts are composed of cations and anions, which can be derived from strong or weak acids and bases. Cations from strong bases and anions from strong acids typically do not affect pH, resulting in a neutral solution. Conversely, cations from weak acids or anions from weak bases can lead to acidic or basic solutions, respectively, depending on their ability to donate or accept protons in solution.

pH Scale

The pH scale measures the acidity or basicity of a solution, ranging from 0 (very acidic) to 14 (very basic), with 7 being neutral. A solution is considered acidic if it has a pH less than 7, basic if greater than 7, and neutral at exactly 7. Understanding the pH scale is essential for interpreting the results of salt hydrolysis and determining the nature of the resulting solution.