In which solution would a #pH>7# be measured: #"A. Phosphoric acid;"# #"B. sodium fluoride;"# #"C. hydrogen chloride;"# #"D. sodium bromide."#?

1 Answer
Aug 18, 2016

Answer:

#"Option B"#

Explanation:

Let's use an example. say hydrogen fluoride, the which in water behaves as a moderately strong acid, due to (i) the strength of the #HF# bond, and the polarizing power of the #F^-# ion.

#HF(aq) + NaOH(aq) rightleftharpoons NaF(aq) +H_2O(aq)#

If such a neutralization occurred, the solution would be stoichiometric in sodium fluoride. This would be involved in water hydrolysis:

#F^(-) + H_2O rightleftharpoons HF(aq) + HO^-#

The presence of small quantities of hydroxide ion would bump up #pH# above #7# at equilibrium.