# CHM135H1 Exam Solutions Fall 2018: Magnesium Oxide, Electronegativity, Magnetic Quantum Number

## Document Summary

Avogadro"s number is the number of atoms, molecules, etc. in 1 mole of a substance. Don"t forget that the group numbers in the periodic table tell how many valence electrons each element in that group has. Part a: the correct answer is c. 1 mole of a molecule contains avogadro"s number of formula units of that molecule. To convert grams to moles, divide the number of grams given by the molecular weight of the molecule. Thus, if there are the same number of grams of a molecule as its molecular weight, then there will be avogadro"s number of formula units of that molecule: the correct answer is d. The principle quantum number (n) is given by the atomic level of the orbital. In this case, n = 6 for a 6d orbital. The angular momentum quantium number (l) is for a d orbital is equal to 2.