Unit 8 Stoichiometry

The Mole Mole (mol): SI unit for measuring the amount of a substance. Avogadro’s Number: 6.02 x 1023

The Mole - examples 1 mole of Helium = 6.02 x 1023 atoms 1 mole of Oxygen = 6.02 x 1023 molecules O2 1 mole of H2O = 6.02 x 1023 molecules H2O

Mole Conversions How many molecules are in 4 moles of H2 gas? 2. 5 x 1027 atoms = _______________ moles

Mole Conversions cont. 9.2 moles F2 = _______________ molecules 2. How many atoms in the F2 molecules?

Mole Conversions cont. 3.4 moles C2H4 = ________ atoms

Mole Conversion practice cont. 0.45 mole He = ________atoms 2. 7.6 x 1023 molecules CH4 = ________moles 3. 15 moles H2O = __________ atoms

Molar Mass Molar Mass: The mass of one mole of an element or compound. Molar mass of a compound = the sum of the masses of the atoms in the formula Use the atomic masses in grams on the periodic table.

Molar Mass The molar mass of water - H2O Mass of Hydrogen 2 x 1.008 = 2.016 Mass of Oxygen = 16.00 Molar mass of water 18.016 grams/mol

Molar Mass Find the molar mass of the following: MgBr2 Ba(OH)2

Molar Mass cont. Find the molar mass of the following compounds: Ba3(PO4)2 C6H12O6

Mole/Gram conversions Molar mass is grams per mol, so we can determine the number of grams in a given amount. To convert from Moles to grams, multiply the moles by the molar mass to get grams. Ex. .033 mol H2O = _______ g .033 mol x 18.016 g = 1 mol

Mole/Gram Conversions Convert the following: How many grams are in 0.27 mol of Ba(OH)2