If The $\left[ \mathrm { OH } ^ { - } \right]$

Multiple Choice

If the $\left[ \mathrm { OH } ^ { - } \right]$ concentration is equal to 0.023M and the analytical concentration of the same base is equal to 0.494 M, its percentage ionization is _____.

A) 4.7%
B) 2.6%
C) 3.5%
D) 6.8%
E) 8.2%