Mass of Mg, g Moles of Mg Moles of H₂ Initial syringe reading, mL Final syringe reading, mL Volume H₂ collected, mL (Final reading - initial reading) Volume H₂ collected, L

Temperature, °C Temperature, K Barometric pressure, mmHg Vapor pressure of H₂O, mmHg Corrected pressure, mmHg Corrected pressure, atm Calculated R value, L-atm/mol-K Average R value, L-atm/mol-K True value of R, L-atm/mol-K % error of average R 1 71 2 Determination 3 4