Question

Select the pair of substances in which an acid is listed followed by its conjugate base. A) H+, HCl

B) NH3, NH4+

C) HPO42-, H2PO4-

D) HCO3-, CO32-

E) CH3COOH, CH3COOH2+

Answer 1

ANSWER =B,C,D,E

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Assuming these acids/bases are all in solution, we can use the Arrhenius definition to define them:

Acid: Substance that dissolves in water to produce H+ ions.

Base: Substance that dissolves in water to produce OH- ions.

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A) H+ + Cl- --> HCl (no acid-base pair here)

B) NH3 + H+ --> NH4+ (This also shows ammonia (NH3) acting as a base)

C). HPO42- + H+ --> H2PO4- (this shows hydrogen phosphate acting as a base)

D) HCO3- --> CO32- + H+ (HCO3- dissolving to give H+ ion, CO32- is its conjuaget base)

E) CH3COOH + H+---> CH3COOH2+ (Acetic acid (CH3COOH) is accepting a H+ base, and CH3COOH2+ is its conjugate acid)

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