To get from pOH to OH- concentration, use the formula OH- = 2nd log (-pOH.) Your calculations should look like… OH- = 2nd long (-pOH) OH-= 2nd log (-11.06) OH-= 8.71 e -12 If you clicked answer "A" then you found the pH. If you clicked answer "B" then you forgot to plug in the negative pOH.