Which of the following statements is false? (a) An Arrhenius base increases the concentration of OH- in water. (b) A Brønsted-Lowry base is a proton acceptor. (c) Water can act as a Brønsted–Lowry acid. (d) Water can act as a Brønsted–Lowry base. (e) Any compound that contains an –OH group acts as a Brønsted-Lowry base.

Verified step by step guidance

1. Identify the definitions of Arrhenius and Brønsted-Lowry acids and bases.
2. Recall that an Arrhenius base increases the concentration of OH^- ions in water.
3. Understand that a Brønsted-Lowry base is defined as a proton (H^+) acceptor.
4. Recognize that water (H2O) can act as both a Brønsted-Lowry acid (proton donor) and a Brønsted-Lowry base (proton acceptor).
5. Evaluate the statement that any compound with an –OH group acts as a Brønsted-Lowry base, and consider exceptions such as alcohols, which do not typically act as bases.

Key Concepts

Arrhenius Theory of Acids and Bases

The Arrhenius theory defines acids as substances that increase the concentration of hydrogen ions (H+) in aqueous solution, while bases increase the concentration of hydroxide ions (OH-). This theory is foundational in understanding the behavior of acids and bases in water, particularly in identifying how they dissociate and interact in solution.

Brønsted-Lowry Theory of Acids and Bases

The Brønsted-Lowry theory expands the definition of acids and bases beyond aqueous solutions. According to this theory, an acid is a proton donor and a base is a proton acceptor. This concept allows for a broader understanding of acid-base reactions, including those that occur in non-aqueous environments.

Amphoteric Substances

Amphoteric substances are those that can act as either an acid or a base depending on the context of the reaction. Water is a prime example, as it can donate a proton (acting as an acid) or accept a proton (acting as a base). Understanding this dual behavior is crucial for analyzing reactions involving water and other amphoteric compounds.