1.Why was it necessary to heat to constant mass? 2. What theoretical mass of oxygen was required to combine with the amount of magnesium that was

1.Why was it necessary to heat to constant mass?

2. What theoretical mass of oxygen was required to combine with the amount of magnesium that was supplied for the reaction? Explain how you figured that out. Hint(2Mg+o2------2MgO)

3. Based on your percent yield, describe one possible error that could have occurred in your experiment. Explain what could have been done, if anything, to prevent the error.Hint: (percent yield92.32%)