Give one standard test of carbon dioxide and also write the equation involved is it a physical or a chemical change ? what is the answer for this

Does anyone know a lot about how to: - calculate mass of magnesium metal - calculate the actual yield of magnesium oxide - calculate the theoretical yield of mgo - calculate the percent yield of mgo - determine the percent yield of mgo - determine the average percent yield of mgo i had to do an online lab and its asking these questions but i have no idea where to start or how to be able to find these things. i can post the chart of the data from the lab or if you can tell me exactly how i can find each.

Describe the particles of all three phases of matter in the root beer float. (how are the particles arranged and moving? )

Which type of bond is present in hydrogen sulfide (h2s)? the table of electronegativities is given. a. hydrogen b. ionic c. nonpolar covalent d. polar covalent