Magnesium combines with oxygen to make magnesium oxide. If 10.57 g of magnesium reacts with 6.96 g of oxygen, what is the percent by mass of oxygen in magnesium oxide?

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Compare and contrast solutions and suspensions

In a heat engine of 1000 j of heat enters the system and the piston does 500 j of work what is the final internal energy of the system if the inital energy was 2000 j we have to do all of these down here 1)write the equation 2)list out your know variables 3)plug the numbers into the equations 4)solve 5)write your solution statemtn that includes inital energuy and final energuy added