posted by Duane .
A student reacts 0.1212 g of an Mg/NaCl mixture with hydrochloric acid. The volume of hydrogen saturated with water vapor collected at 20.0C was measured to be 42.7 ml. The column of water that remained in the buret was 10.3 cm high. If vapor pressure of water = 17.5 mmHg at this temperature and the barometric pressure was 763 mmHg, what is the % Mg in the sample?