Compounds - Mark Rosengarten

3) Formula Mass Homework
A) Determine the number of moles of each element present in one mole of each of the following compounds:
Formula Number of: Number of: Number of:
NaCl Na: Cl:
CaBr 2 Ca: Br:
K 2 SO 4 K: S: O:
Fe 2 (CO 3 ) 3 Fe: C: O:
SO 3 S: O:
CH 3 COOH C: H: O:
B) Determine the total number of moles of atoms in the following formulas:
Formula
Total Number of
Moles of Atoms
Formula
Total Number of
Moles of Atoms
Formula
Total Number of
Moles of Atoms
NaCl
2 NaNO 3 4 (NH 3 ) 2 SO 4
Pb 3 (PO 4 ) 2 3 K 2 Cr 2 O 7
MgSO 4
C) Identify each of the following as an empirical or molecular formula. If a formula is molecular, write its
empirical formula.
Formula
Empirical or
Molecular?
Simplify if
Molecular
Formula
NaCl N 2 O 4
Empirical or
Molecular?
Simplify if
Molecular
C 2 H 6 Ra(CN) 2
Ba(NO 3 ) 2 C 6 H 12 O 6
D) Identify each statement as having been determined from quantitative or qualitative analysis.
1) The compound consists of carbon, hydrogen, and chlorine.
2) In a molecule of this compound, there are 6 atoms of carbon, four atoms of hydrogen, and two atoms of chlorine.
© 2011, Mark Rosengarten AE 30