Question

\(\mathrm{A}(\mathrm{n}) \) ________ can help keep the \(\mathrm{pH}\) of a solution stable. a. covalent bond b. hydrogen bond c. buffer d. \(\mathrm{pH}\)

Short answer

The correct answer is c. buffer.

Step-by-step solution

Identify Key Terms

Analyze the question to identify key terms and concepts. Here, the focus is on the term 'keep the \(\mathrm{pH}\) of a solution stable.' This phrase implies a mechanism or substance that can neutralize or resist changes in \(\mathrm{pH}\) levels.

Understand Each Option

Examine each provided option to understand its role in chemistry: a. A covalent bond is a chemical bond where atoms share pairs of electrons. b. A hydrogen bond is a weak attraction between a slightly positive hydrogen atom and a slightly negative atom. c. A buffer is a solution that resists changes in \(\mathrm{pH}\) upon the addition of acids or bases. d. \(\mathrm{pH}\) is a measure of the hydrogen ion concentration of a solution.

Evaluate Options Against Criteria

Determine which option fulfills the requirement of keeping \(\mathrm{pH}\) stable: - Covalent bonds and hydrogen bonds are types of chemical bonds, and do not stabilize \(\mathrm{pH}\). - \(\mathrm{pH}\) describes acidity, not a stabilizer. - A buffer's primary role is to maintain a stable \(\mathrm{pH}\), making it ideal for stabilizing acidity levels in a solution.

Key concepts

pH stability

The concept of pH stability is crucial when discussing the behavior of solutions, particularly in biological and chemical environments. When we refer to pH stability, we're talking about the ability of a solution to maintain its pH level, even when changes occur in the surrounding conditions. In a stable pH environment, the solution resists drastic pH changes, ensuring a consistent environment that is essential for many biochemical processes. 

Buffers play a key role in maintaining pH stability. They do so by absorbing excess hydrogen ions (H⁺) when the solution becomes too acidic and donating them back when it becomes too basic. This buffering action happens because buffers usually consist of a weak acid and its conjugate base, which can interchange protons according to the surrounding concentration of H⁺ ions. 

A stable pH is vital for:

• Maintaining enzyme activity: Enzymatic reactions often have an optimal pH range.
• Ensuring cellular function: Cells require a consistent pH to function correctly.
• Supporting metabolic processes: Many metabolic pathways depend on specific pH conditions.

Overall, understanding pH stability helps ensure either the desired chemical or biological outcome.

acid-base balance

The balance of acids and bases is an integral part of chemistry, critical for various processes in biological systems and industrial applications. This balance determines whether a solution is acidic, basic, or neutral. Maintaining this balance is essential as it influences the chemical reactivity and properties of the solution.
The significance of acid-base balance is often highlighted in biological contexts, such as within the human body. The human body, for example, operates optimally at a relatively constant pH of around 7.4. To maintain this balance, physiological systems use buffers like bicarbonate to neutralize excess acids or bases.
Within the scope of chemistry, the importance of buffers in managing acid-base balance cannot be overstated. A buffer solution consists typically of a weak acid and its conjugate base, or a weak base and its conjugate acid. Here's how they work:

• When an acid is added, the conjugate base in the buffer solution will neutralize it, preventing pH changes.
• Conversely, when a base is added, the weak acid will neutralize the base, again maintaining the pH.

Understanding acid-base balance is crucial for effective chemical management and essential for sustaining life.

chemical equilibrium

Chemical equilibrium is a pivotal concept in understanding how reactions take place and are balanced in a system. At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction, leading the concentrations of reactants and products to remain constant. However, this does not imply the amounts are equal, just that their levels no longer change with time.
In the context of buffers, chemical equilibrium is crucial as buffers maintain their ability to stabilize pH by establishing equilibrium between the weak acid and its conjugate base or vice versa. This equilibrium enables the solution to absorb or release hydrogen ions without significant shifts in pH.
The principle of Le Chatelier also plays a vital role here, stating that if a system at equilibrium is disturbed, it will shift to minimize that disturbance. For example:

• When extra H⁺ ions are added to a buffer, the equilibrium shifts to consume these ions, minimizing changes in pH.
• When OH^- ions are introduced, the buffer provides H⁺ ions from its acidic component to balance the increase in base.

Chemical equilibrium is therefore a fundamental aspect of buffer function, essential for understanding how stable chemical systems behave.