Understanding Acid-Base Equilibria

What is the definition of an acid according to the Brønsted-Lowry theory?

• A Brønsted-Lowry acid is a substance that increases pH.

• A Brønsted-Lowry acid is a proton donor.

• A Brønsted-Lowry acid is a molecule that donates electrons.

• A Brønsted-Lowry acid is a proton acceptor.

Explain the concept of pH and how it relates to hydrogen ion concentration.

• pH is inversely related to hydrogen ion concentration; as [H+] increases, pH decreases.

• pH is directly proportional to hydrogen ion concentration.

• pH increases as hydrogen ion concentration increases.

• pH has no relation to hydrogen ion concentration.

What is the difference between a strong acid and a weak acid?

• Strong acids are always more concentrated than weak acids.

• Weak acids have a higher pH than strong acids.

• Strong acids are less corrosive than weak acids.

• Strong acids fully dissociate in solution; weak acids partially dissociate.

Describe the role of a conjugate base in acid-base reactions.

• A conjugate base accepts protons and can participate in reverse reactions.

• A conjugate base has no role in chemical reactions.

• A conjugate base is always a strong acid.

• A conjugate base donates protons to acids.

How does Le Chatelier's principle apply to acid-base equilibria?

• Le Chatelier's principle applies to acid-base equilibria by predicting how the equilibrium will shift in response to changes in concentration, temperature, or pressure.

• Le Chatelier's principle states that equilibrium cannot be shifted.

• Le Chatelier's principle only applies to gas reactions.

• Acid-base equilibria are unaffected by temperature changes.

What is the significance of the acid dissociation constant (Ka)?

• It measures the temperature of an acid solution.

• It determines the solubility of an acid in water.

• The significance of the acid dissociation constant (Ka) is that it indicates the strength of an acid in solution.

• It indicates the color change of an acid in a pH indicator.

How do buffers work to maintain pH in a solution?

• Buffers work by increasing the concentration of hydrogen ions.

• Buffers maintain pH by neutralizing added acids or bases through equilibrium reactions.

• Buffers change the temperature of a solution to affect pH.

• Buffers only absorb excess water in a solution.

What is the relationship between pKa and Ka?

• Ka = 10^(-pKa)

• pKa = log10(Ka)

• pKa = Ka + 1

• pKa = -log10(Ka)

Explain how titration can be used to determine the concentration of an acid or base.

• Titration can determine the concentration of an acid or base by using a titrant of known concentration to reach a reaction endpoint, allowing calculation of the unknown concentration.

• Titration involves mixing equal volumes of acid and base to find concentration.

• Titration measures temperature changes to determine concentration.

• Titration uses a color indicator to estimate the concentration without calculations.

What factors can affect the position of an acid-base equilibrium?

• Color of the solution

• Type of glassware used

• Concentration, temperature, pressure, and presence of catalysts.

• Time of day when the reaction occurs