Calculate the mass of Mg in 380g of Magnesium oxide

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.

Label a-f based on the table using c for concentrated and d for dilute

How many grams of oxygen gas are contained in a 15 l sample at 1.02 atm and 28°c? show your work.