Acid & Base Definitions

The correct answer is Lewis. Lewis acid-base theory defines an acid as a species that can accept electron pairs. This theory focuses on the transfer of electrons during acid-base reactions, with the acid being the electron acceptor and the base being the electron donor. Unlike the Arrhenius and Bronsted-Lowry definitions, which focus on the presence of hydrogen ions in acids, the Lewis definition is broader and includes species that can accept electron pairs regardless of the presence of hydrogen ions. Svante is not a recognized acid-base theory, so it is not the correct answer.

An Arrhenius base is defined as a substance that, when dissolved in water, produces hydroxide ions (OH-) and acts as an OH- donor. This definition distinguishes Arrhenius bases from other options such as substances that can donate a proton or accept electron pairs. Arrhenius bases specifically produce OH- ions when dissolved in water, allowing them to increase the concentration of hydroxide ions in a solution.

The Bronsted-Lowry definition of a base states that it is any substance that can accept a hydrogen ion (H+). This definition is different from the Arrhenius definition, which defines a base as a substance that produces hydroxide ions (OH-) in water, and the Lewis definition, which defines a base as any electron pair donor. The Bronsted-Lowry definition is more inclusive as it allows for bases that do not necessarily need to be in water or produce hydroxide ions.

A Bronsted-Lowry base is defined as any substance that can accept H+ ions (protons). This means that when a Bronsted-Lowry base reacts with an acid, it accepts a proton from the acid, forming a new compound. The base acts as a proton acceptor in the reaction. This definition is different from the other options because it focuses on the ability of a substance to accept protons, rather than donate or produce them.

An Arrhenius acid is defined as a substance that, when dissolved in water, dissociates to form hydrogen ions. This means that it releases H+ ions into the solution. This is in contrast to an Arrhenius base, which would instead release hydroxide ions (OH-) when dissolved in water. Therefore, the correct answer is "a substance that when dissolved in water dissociates to form hydrogen ions."

A Lewis base is a species that can donate a pair of electrons. In the given options, the only choice that fits this definition is "any species with lone pairs on the central atom." This is because species with lone pairs on the central atom have the ability to donate those electrons, making them good Lewis bases. The other options, such as H3O+, refer to species that can accept electrons or donate or accept H+ ions, which do not fit the definition of a Lewis base.