The Mole Concept
The Mole Measures the amount of a substance Relates to the number of particles, mass, and volume of a substance
The Mole Avogadro’s Number 6.02 x 1023 particles = 1 mole Particles = atoms, molecules, or formula units
The Mole 1 mole of Fe = ? atoms 1 mole of H2O = ? molecules 1 mole of CaCl2 =? Formula units
The Mole How many moles is 1.25 x 1023 atoms of Mg?
The Mole How many C atoms are in 2.12 mole of propane C3H8?
Gram Atomic Mass atomic mass of an element expressed in grams/mol Found on the PT rounded to 1 decimal place
Gram Atomic Mass
Gram Atomic Mass What is the gam of N, O, H, Na, Cl?
Mole-Mass Relationships Molar Mass – mass in grams of 1 mole of a substance What is the molar mass of H2O2? (NH4)2CO3?
Summary/Warmup What conversion is used between moles and particles? How is Molar Mass calculated?
Mole-Mass Relationships What is the molar mass of oxygen? How many grams are in 3.0 mol of oxygen? How many moles are in 2.30g of oxygen?
Mole-Volume Relationships Molar Volume – At STP, the volume of 1 mole of any gas is 22.4L STP – Standard Temperature (0oC) and Standard Pressure (1 atm)
Mole-Volume Relationships Determine the volume in Liters of 0.60 mol of SO2 at STP.
Complex Mole Conversions How many grams are in 3.48x1023 formula units of iron(III)oxide?
Complex Mole Conversions How many atoms are in 10.0 L of Argon gas at STP?
Complex Mole Conversions How many atoms of Zinc are in 10.0g of Zn?
Complex Mole Conversions How many molecules are in 718g dinitrogen trioxide?
Complex Mole Conversions What is the volume of 2.00g of water at STP?
Why was the mole of oxygen molecules excited when he left the singles bar? He got Avogadro's number!
Mole Relationships
Percent Composition
Percent Composition %mass of an element =g element/ g compound x 100
Percent Composition An 8.20g piece of Mg combines completely with 5.40g of O to form a compound. What is the percent composition?
Percent Composition If only the chemical formula of the compound is known divide the mass of each element in a mole of a compound by the molar mass and multiply by 100
Percent Composition Calculate the percent composition of C3H8
Emperical Formula Gives the lowest whole number ratio of atoms of elements in a compound May or may not be the same as the molecular formula
Emperical Formula What is the ef of a compound that is 25.9% N and 74.1% O
Molecular Formulas Is either the same as the ef or a whole number multiple of it Determined from ef and molar mass of the mf MM of mf/ MM of ef = whole number multiple
Molecular Formulas Calculate the molecular formula of the compound whose molar mass is 60.0g/mol and emperical formula is CH4N.
Putting it all together Determine the ef and mf of Caffeine which contains 49.5%C, 5.15%H, 28.9%N, and 16.5%O; and the molar mass is 195g/mol.
Putting it all together Determine the ef and mf of Ibuprofen which contains 75.69%C, 8.80%H, and 15.51%O ; and the molar mass is 206g/mol.