Name_____________________________________ Friday, December 18, 2015
Section I: Calculate the molar or formula mass of each of the following
1.
Calculate the molar mass of C
6
H
5
Cl
2.
Calculate the molar mass of CaCO
3
3.
Calculate the formula mass of FeSO
4
4.
Calculate the molar mass of Fe(OH)
3

Section II: Determining Percent Composition – Calculate the percent by mass of each of the elements in the compounds below .
1.
Calculate the percentage composition of baking soda NaH(CO
3
)
2
Na____________, H____________, C____________, O____________
2.
Calculate the percentage composition of Na
2
CO
3
Na____________, C____________, O____________
Section IV: Empirical & Molecular Formulas –
Determine the Empirical Formula from each of the following Molecular Formulas
1.
Na
2
C
2
O
4
_________________________
2.
C
6
H
4
(NO
3
)
2
_______________________
3.
C
3
H
6 ____________________________________________
4.
CH
3
COOH ________________________
5.
Find the molecular formula for a compound with a mass of 78g and the empirical formula CH.
6.
Find the molecular formula for a compound with a mass of 90g and the empirical formula HCO
2
.
7.
Find the molecular formula for a compound with a mass of 80g and the empirical formula C
3
H
4
.

Section V: Molar Calculations
1) How many moles of KClO
3 are in 400g?
2) How many molecules KClO
3
are in 3 moles?
3) How many moles are in in 8.0 x 10 24 molecules of KClO
3
?
4) How many molecules are there in 500g of KClO
3
?
5) How many grams of AlCl
3
would result from 7.9 moles?
6) How many grams of AlCl
3 are in 4 x 10 23 molecules?