12. if each orbital can hold a maximum of two electrons, how many electrons can each of the following hold?
a.
b. 2s c. 5p d. 4f e. 3d f. 4d
for the following electron configurations choose 3 possible elements (or ions) they may represent
1. 1s2 2s22p6 3s23p6 4s2 3d10 4p4
2. 1s2 2s22p6 3s23p6 4s2 3d10 4p5
3. 1s2 2s22p6 3s23p6 4s2 3d10 4p6
4. 1s2 2s22p6 3s23p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s1
5. 1s2 2s22p6 3s23p6 4s2 3d10 4p6 5s24 d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d8

Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?

These questions are based on the attached photo. the experiment is about burning magnesium metal with oxygen. 1. write the balanced chemical equation for the reaction you are performing. 2. calculate the mass of magnesium metal used in each trial. o trial 1: o trial 2: 3. calculate the actual yield of magnesium oxide for each trial. o trial 1: o trial 2: 4. magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. o trial 1: o trial 2: 5. determine the percent yield of mgo for your experiment for each trial. o trial 1: o trial 2: 6. determine the average percent yield of mgo for the two trials. your company currently uses a process with a similar cost of materials that has an average percent yield of 91 percent. if the average percent yield of this process is higher than that, this could save the company money. what is your recommendation to the company? support your recommendation using your data, calculations, and understanding of stoichiometry gathered from this lab.