Final answer:
The statement that weak acids and bases can be written in equilibrium form is true. They only partially dissociate in water, creating an equilibrium between undissociated molecules and produced ions, described by an equilibrium chemical equation and characterized by an acid-ionization constant (Ka) or base-ionization constant (Kb).
Step-by-step explanation:
The statement that weak acids and bases can be written in equilibrium form is true. Weak acids and bases only partially dissociate in water, establishing a dynamic equilibrium between the undissociated molecules and the ions they produce. For example, the partial ionization of weak acid hydrofluoric acid (HF) in water can be represented by the following equilibrium chemical equation:
HF(aq) + H₂O(l) ⇌ H3O+(aq) + F-(aq)
Similarly, for a weak base like silver hydroxide (AgOH), the equilibrium can be represented as:
AgOH(aq) ⇌ Ag+(aq) + OH-(aq)
And for methylamine (CH₃NH₂), a weak base, the equilibrium is:
CH₃NH₂(aq) + H₂O(l) ⇌ CH₃NH3+(aq) + OH-(aq)
In contrast to strong acids and bases, which ionize completely in solution, weak acids and bases have an acid-ionization constant (Ka) for weak acids, and typically a base-ionization constant (Kb) for weak bases, which are measures of their strength and degree of ionization in solution.