1. What is the meaning of equilibrium?
Answer: Equilibrium refers to a state of balance in which opposing forces or processes are in perfect balance.
2. Explain the concept of dynamic equilibrium.
Answer: Dynamic equilibrium occurs in reversible reactions where the rates of the forward and reverse reactions are equal, resulting in no net change in the concentrations of reactants and products over time.
3. Describe the equilibrium involving physical processes.
Answer: Equilibria involving physical processes include solid-liquid, liquid-gas, and solid-gas equilibria. These processes involve phases of matter reaching a balance in which the rates of phase change in both directions are equal.
4. What is Henry’s law and its significance?
Answer: Henry’s law states that the concentration of a gas in a liquid is directly proportional to the partial pressure of that gas above the liquid. Its significance lies in its application to various phenomena like gas solubility in liquids.
5. Define equilibrium constants (K) for chemical processes.
Answer: Equilibrium constants (K) are expressions representing the ratio of product concentrations to reactant concentrations at equilibrium for a chemical reaction. They indicate the extent of the reaction and are used to calculate equilibrium concentrations.
6. Explain the Law of Chemical Equilibrium.
Answer: The Law of Chemical Equilibrium states that in a closed system at equilibrium, the ratio of the concentrations of products to reactants, raised to the power of their respective stoichiometric coefficients, is a constant at a given temperature.
7. What is the significance of equilibrium constant (K)?
Answer: The equilibrium constant (K) indicates the position of equilibrium and the relative amounts of reactants and products at equilibrium. It helps predict the direction of a reaction and the concentrations of substances at equilibrium.
8. Discuss the significance of ΔG° in chemical equilibrium.
Answer: ΔG° (standard Gibbs free energy change) indicates whether a reaction is spontaneous or non-spontaneous at standard conditions. In equilibrium, ΔG° = 0, signifying that the system is at equilibrium.
9. Name the chemical factors affecting equilibrium and explain their influence.
Answer: Pressure, temperature, and catalysts affect chemical equilibrium. Pressure affects equilibrium involving gases, temperature influences the endothermic or exothermic nature of the reaction, and catalysts alter the rate of the forward and reverse reactions, but not the position of equilibrium.
10. What is Le Chatelier’s Principle?
Answer: Le Chatelier’s Principle states that if a system at equilibrium is subjected to a stress, it will adjust to counteract the stress and establish a new equilibrium position.
11. Differentiate between weak and strong electrolytes.
Answer: Weak electrolytes partially dissociate into ions in solution, while strong electrolytes completely dissociate into ions.
12. Define acids and bases in terms of ionization.
Answer: Acids donate protons (H⁺ ions) in solution, while bases accept protons. In terms of ionization, acids ionize to release H⁺ ions, while bases ionize to release OH⁻ ions or accept H⁺ ions.
13. Explain the concept of pH and its effect.
Answer: pH is a measure of the acidity or basicity of a solution, defined as the negative logarithm of the hydrogen ion concentration. It indicates the concentration of H⁺ ions in a solution and affects various chemical and biological processes.
14. Discuss the hydrolysis of salts and its significance.
Answer: Hydrolysis of salts occurs when salts react with water to produce acidic or basic solutions. It’s significant in understanding the pH of salt solutions and their behavior in aqueous environments.
15. What are buffer solutions?
Answer: Buffer solutions are solutions that resist changes in pH upon addition of small amounts of acid or base. They contain a weak acid and its conjugate base, or a weak base and its conjugate acid.
16. Explain the common ion effect.
Answer: The common ion effect is the suppression of the ionization of a weak electrolyte by the presence of a common ion, either from the dissociation of another electrolyte or from the addition of a soluble salt.
17. Define solubility product (Ksp) and its importance.
Answer: Solubility product (Ksp) is the equilibrium constant for the dissolution of a sparingly soluble salt in water. It quantifies the degree of solubility of the salt and helps predict whether a precipitate will form.
18. Discuss the ionization of water and its significance.
Answer: Ionization of water involves the autoionization of water molecules into hydronium (H₃O⁺) and hydroxide (OH⁻) ions. It’s significant in determining the pH of pure water and understanding acid-base chemistry.
19. Differentiate between Arrhenius, Bronsted-Lowry, and Lewis acid-base theories.
Answer: Arrhenius theory defines acids as substances that release H⁺ ions in solution and bases as substances that release OH⁻ ions. Bronsted-Lowry theory defines acids as proton donors and bases as proton acceptors. Lewis theory defines acids as electron pair acceptors and bases as electron pair donors.
20. Explain the concept of multistage ionization in acid-base reactions.
Answer: Multistage ionization refers to the sequential donation or acceptance of protons in a polyprotic acid or base. It results in the formation of multiple conjugate acid-base pairs and affects the pH of the solution at each stage.