Final answer:
In the Brønsted-Lowry theory, acids and bases do have conjugates: an acid forms a conjugate base after donating a proton, and a base forms a conjugate acid after accepting a proton.
Step-by-step explanation:
Lewis acids and bases differ from Brønsted-Lowry acids and bases in that the Lewis definition is more general, focusing on electron pairs rather than protons. Lewis acids accept electron pairs, whereas Lewis bases donate electron pairs. However, in the context of the Brønsted-Lowry theory, when an acid donates a proton (H+), it forms a conjugate base, and when a base accepts a proton, it forms a conjugate acid. For example, when the hydrogen sulfate ion (HSO4-) donates a proton, it becomes the sulfate ion (SO42-), which is its conjugate base. The strengths of acids and bases are often related to their conjugates; strong acids have weak conjugate bases, and weak acids have strong conjugate bases. This is because strong acids are completely ionized in solution, leaving behind a conjugate base that is a weak base. Strong acids have weak conjugate bases, while weak acids have strong conjugate bases.
Yes, Lewis acids and bases have conjugate acids and conjugate bases. In the Lewis acid-base theory, a Lewis acid is a species that accepts a pair of electrons, while a Lewis base is a species that donates a pair of electrons. When a Lewis acid accepts a pair of electrons, it forms a complex with the Lewis base, generating a conjugate acid and a conjugate base. The conjugate acid is formed by the addition of a proton, while the conjugate base is formed by the loss of a proton. For example, in the reaction between boron trifluoride (BF3) and ammonia (NH3), BF3 acts as a Lewis acid, accepting a pair of electrons from NH3, which acts as a Lewis base. The resulting complex is NH3...BF3, with NH3 as the conjugate base and BF3 as the conjugate acid.