Bronsted vs Arrhenius Base: J.1(c) and (e)

[Hannah Lee 2F]

Identify each compound as either a Brønsted acid or a Brønsted base: (c) KOH; (e) Ca(OH)2.

It is clear that both KOH and Ca(OH)2 are bases since they are metal hydroxides. However, to align with the Bronsted definition, how would KOH and Ca(OH)2 accept a proton?

Do we have to conform to just the Bronsted definition of an acid in base, or are the Bronsted and Arrhenius definitions used interchangeably? For instance, in the case of KOH and Ca(OH)2, they technically do not align to the Bronsted definition of a base because it doesn't accept a proton, it just supplies the OH-.

[ALegala_2I]

The OH- in both compounds with accept a proton to create water. Since it is accepting protons, these compounds conform to the definition of a Bronsted base.

[PranaviKolla2B]

What is the definition of an Arrhenius base?

[Hannah Lee 2F]

Thank you! It makes sense now :)

And an Arrhenius base is a species that produces hydroxides (OH-) in water. It is restrictive because it does not account for species that produce OH- in solutions other than water, so we normally go with the Bronsted definition.