Which of the following acid/base pairs yields the most nearly neutral aqueous solution when mixed?
b) H2CO3/2 NaOH
a) incorrect, strong acid + weak base forms NaCl and HF, the HF hydrolyzes to H3O+ and F–, pH<7
b) incorrect, weak acid + strong base forms Na2CO3 + 2 H2O, and the CO32- ion autoionizes water, to create OH– ions, pH>7
c) correct, strong acid + strong base forms NaCl + H2O and salt ions do not react with water to change pH, pH=7
d) incorrect, strong acid + weak base forms NH4Br, the NH4+ ions weakly dissociates to NH3 + H+ and Br– does not react with water, pH<7
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