Molar Mass worksheet KEY
Determine the molar mass for the following elements:
Ca Xe K
40.08 g Ca 131.29 g Xe 39.10 g K
Fe Au O
55.85 g Fe 196.97 g Au 16.00 g O
Determine the molar mass for the following molecules/compounds
NaCl H2O O2
22.99 + 35.45 2(1.01) + 16.00 2(16.00)
58.44 g NaCl 18.02 g H2O 32.00 g O2
Fe2O3 Na2O Cl2
2(55.85) + 3(16.00) 2(22.99) + 16.00 2(35.45)
159.70 g Fe2O3 61.98 g Na2O 70.90 g Cl2
Determine the mass of the following samples
2 moles Co 5 moles H2 2.1 moles H2O
2 mol Co (58.93 g Co/1 mol Co) 5 mol H2 (2.02 g H2/1 mol H2) 2.1 mol H2O (18.02 g H2O /1 mol
H2O)
117.86 g Co 10.10 g H2 37.84 g H2O
Determine the number of moles in the following samples
54.2 g N2 202.2 g MgO 519.3 g FeCl3
54.2 g N2 (1 mol N/28.02 g N2) 202.2 g MgO (1 mol MgO/40.31 g MgO) 519.3 g FeCl3(1 mol N/162.20 g FeCl3)
1.93 mol N2 5.02 mol MgO 3.20 mol FeCl3
Determine how many atoms/molecules in the following samples
1.32 moles Si
1.32 moles Si (6.022X1023 atoms/1 mol Si)
7.95X1023 atoms Si
7.29 mol CO
7.29 mol CO(6.022X1023 molecules/1 mol CO)
4.39X1024 molecules CO
712.4 g AuCl
712.4 g AuCl (1 mol AuCl/232.42 g AuCl) (6.022X1023 molecules/1 mol AuCl)
1.85X1024 molecules AuCl
