If 62.0 grams of magnesium metal (Mg) react with 55.5 grams of oxygen gas (O2) in a synthesis reaction, how many grams of the excess reactant will be left over when the reaction is complete?

Be sure to write out the balanced equation for this reaction and to show all of your work.

Question

If 62.0 grams of magnesium metal (Mg) react with 55.5 grams of oxygen gas (O2) in a synthesis reaction, how many grams of the excess reactant will be left over when the reaction is complete? 

Be sure to write out the balanced equation for this reaction and to show all of your work.

anonymous · Answer

2Mg + O2 == 2MgO .. convert grams  into moles ( Mr Mg =24,31 and Mr O=16)  and put it in equation. if there are more oxygen then the moles of magnesium will be the limiting reagent.. $$moles Mg = 62\div24,31 = 2.55 $$$$Moles O2 = 55.5\div32=1.73$$

anonymous · Answer

Thank You! :D