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.) 6.23 grams P to atoms P.
6.2 g
mol
0.
g
6.022
02 atoms
mol
1.211  1023  1.21  10
23
atoms P
2.) 15.66 grams CaBr2 to moles CaBr2.
CaBr2 = (1)(40.08 g/mol) + (2)(79.90 g/mol) = 199.88 g/mol
mole a r2
.66 g a r2
0.078347  0.07835 moles CaBr2
. g a r
2
3.) 0.82 moles FeCl3 to moles Cl.
0. 2 mols e l
moles l
mole e l
2.46  2.5 moles Cl