(Solved): 4) Write an acid-base reaction equation for the addition of \( \mathrm{NaOH}\left(\mathrm{HO}^{-} ...

4) Write an acid-base reaction equation for the addition of \( \mathrm{NaOH}\left(\mathrm{HO}^{-} \mathrm{Na}^{+}\right) \)to \( \mathrm{HC}=\mathrm{CH} \rightarrow \) Use \( \mathrm{pK}_{\mathrm{a}} \) values to predict the direction of the equilibrium. (6 pts) \( \left(\mathrm{HC}=\mathrm{CH}: \mathrm{pK}_{\mathrm{a}}=25 ; \mathrm{H}_{2} \mathrm{O}: \mathrm{pK}_{\mathrm{a}}=15.7\right) \)