I know how to do this problem, but need confirmation regarding precision of calculation involving significant figures.
Information given: 0.010 M morphine solution, pH = 10.10, calculate Kb and pKb, morphine is a weak base
Calculating the [OH-] from the pH given yields an unrounded 1.258E-04 M, but the value accurate to the number of significant figures given from a pH of 10.10 is 1.2E-04 M.
My question is, after going through the necessary ICE table and writing the expression for Kb, is it correct to use the less precise value of [OH-] above, or is it also correct to use the more precise value? Each value yields a different value of Kb: 1.5E-06 and 1.6E-06, respectively to the less precise and more precise value.