What are all 4 levels of the energy pyramid? asap

What does the mass of 0.7891 mol of ferric oxide (fe2o3)

Using the first volume and temperature reading on the table as v1 and t1, solve for the unknown values in the table below. remember to use the rules of significant figures when entering your numeric response.

Inside a flashbulb, oxygen surrounds a thin coil of magnesium. when the flashbulb is set off, a chemical reaction takes place in which magnesium combines with oxygen to form magnesium oxide. which of the chemical equations matches the reaction above? a. mg + o2 mgo2 + energy b. 2mg + o mg2o + energy c. 2mg + o2 2mgo + energy d. mg + o mgo + energy