How to Determine Molar Mass
Molar mass of an element is equal to the atomic
mass of the element from the periodic table, but the
units are different.
The unit for molar mass is grams per mole (g/mol).

The molar mass of potassium is 39.09 g/mol
zinc is 65.39 g/mol
.
Oxygen can be rounded to 16.0 g/mol.
Molar mass of a compound requires a chemical
formula; this is often called formula mass.

The mass of each element in
the formula is added together in the
ratios from the sunscripts the
unit is in grams per mole (g/mol)
Example: H2O
H: 2 × 1.00 g/mol = 2.00 g/mol
O: 1 × 16.0 g/mol = 16.0 g/mol
Total = 18.0 g/mol
Determine the Molar Mass
1.
NaCl
2.
H2 O
3.
O2
4.
Fe2O3
5.
Na2O
6.
Cl2
7.
(NH4)2SO4
8.
Pb(NO3)2
9.
Ga2(SO3)3
Grams/Moles Calculations
1. How many moles are in 30 grams of H3PO4?
2. How many grams are in 5.6 moles of C6H6?
3. How many moles are in 12.3 grams of CO2?
4. How many grams are in 1.2 moles of (NH4)3PO3?
5. How many moles are in 110 grams of NaHCO3?
10. Mg(OH)2
11. Pb(CH3COO)4
12. K2SO4
6. How many grams are in 21.3 moles of BaCO3?