1) How high above the inner blue cone of the burner flame should the crucible be when the Mg is heated?

2) What should you do if you see white smoke rising from the crucible in the early stages of heating the Mg?
3) How will you know when the reaction between Mg and O2 is complete?

1 answer

1. t the top of the blue tip or slightly bove.

2. The while "smoke" is part of the MgO escaping. I would quickly move the crucible cover to completely cover the top and move the burner away for 4-5 seconds to allow all of the MgO smoke to be collected and cooled, then reestablish the heating pattern.