A student plans to determine the pH of a 0.10 M solution of HF (Ka=7.2×10−4) by assuming that the equilibrium concentration of HF remains 0.10 M. Which statement correctly evaluates this assumption?
a) The assumption is acceptable because the percent ionization is less than 5\%.
b) The assumption is acceptable because Ka is small compared with the initial concentration of HF.
c) The assumption is not acceptable because the percent ionization exceeds 5\%.
d) The assumption is not acceptable because HF behaves essentially as a strong acid at 0.10M.