If an enclosure of 0 482 L has a partial pressure of O_2 of 3.4 times 10^-6 torr at 27 degree C, what mass of magnesium will react according to the following equation? 2Mg(s) + O_2(g) rightarrow 2MgO(s) Express your answer using two significant figures. m = 3.4 middot 10^-9