NH₄⁺ and NH₃ represents A Bronsted-Lowry conjugate acid base pair
Explanation:
Conjugate acid to the Bronsted-Lowry base is one that occurs after the proton adopts the base. The two types of acid-base conjugate pair have the same empirical formula, except that the acid has an additional initial text H +, H, final text, plus start and end superscript, relative to the conjugate base.
Conjugate acid / base pair is one in which the pairing species differ in proton. So,concluding that NH₄⁺ and NH₃ would be the right choice. Because here NH₃ becomes NH₄⁺ (accepted one proton of H).
NH₃ + H₂O → NH₄⁺ + OH⁻
Accepting a proton by ammonia from water acts as a Brønsted-Lowry base. Water donates proton to ammonia acts as a Brønsted-Lowry acid.