We did a lab on Le Chatlier's principle. A post-lab question asks wether or not Mg(OH)2 fits the pattern of solids being soluble in warm water. NaOH was added to MgCl2 to provide the OH. The phenolphthalein indicator within the solution changed color with NaOH's addition--magenta. When heated it turned pink. When cold it turned violet. Is the answer to my question that MgOH doesn't fit the pattern, because the indicator said so? because the forward dissociative reaction is exothermic?