Which element has three unpaired electrons in its p orbital? carbon (atomic number 6) oxygen (atomic number 8) nitrogen (atomic number 7) beryllium (atomic number 4)

There are 6.022 x 10^23 atoms of hg in 1 mole of hg. the number of atoms in 4.5 moles of hg can be found by multiplying 4.5 by 6.022 x 10^23 a. 2.7 x 10^24 b. 27 x 10^23 c. 2.71 x10^24 d. 27.099 x 10^23

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

What is the percent by mass of oxygen in fe2o3