if your partner did not take into account the vapor pressure of water when calculating the moles of hydrogen produced, would the mass of Mg that was calculated at the end of the experment be too high or too low
If the partner did not take into account the vapor pressure of water when calculating the moles of hydrogen produced, the mass of Mg that was calculated at the end of the experiment would be too high.
This is because the vapor pressure of water affects the actual amount of hydrogen gas produced. Without considering the vapor pressure of water, the calculated moles of hydrogen would not account for any water vapor present, leading to an overestimation of the moles of hydrogen and, consequently, an overestimation of the mass of magnesium.