When a base is added to a buffered solution, the buffer will .
a. accept water molecules
b. donate OH ions
c. form covalent bonds with the base
d. donate H+ ions

d. donate H+ ions

Explanation:

Mixture of weak acid and its conjugate base or mixture of weak base and its conjugate acid resist the change in pH of the solution when acids or bases are added to them. Such solutions which resist the change in pH on adding acids or bases are called buffer solution.

Buffer solution reverse the effect of addition of acids and bases by neutralizing them.  

So, if base is added, it combines with H+ ions released by buffer solution to form water. Therefore, among the given the correct option is d, donate H+ ions.

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