NAME: ANSWER KEY
Chem20: Quiz #4
The Mole: Recall that Avogadro’s number is 6.022  1023 units = 1 mole (mol). Use this and the
periodic table to convert the following.
1.) 8.26 grams S to atoms S.
mole
.26 g
02 atoms
6.022
2.0 g
mole
1.551  1023  1.55  10
2.) 10.72 grams MgF2 to moles MgF2.
MgF2 = (1)(24.31 g/mol) + (2)(19.00 g/mol) = 62.31 g/mol
0. 2 g
g
mole
2
62.
g 2
g g 2
0.17204  0.1720 moles MgF2
3.) 0.51 moles CH4 to moles H.
0.
moles
moles
mole
2.04  2.0 moles H
23
atoms S