 # Review: Molar Mass of Compounds

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Review: Molar Mass of Compounds
Ex. Molar mass of CaCl2 Avg. Atomic mass of Calcium = 40.08g Avg. Atomic mass of Chlorine = 35.45g Molar Mass of calcium chloride = (2) = _110.98______ g/mol CaCl2 20 Ca  17 Cl 35.45

Practice Calculate the Molar Mass of calcium phosphate Formula =
Ca3(PO4)2 Masses elements: Ca = 40.08g/mole P = g/mole O = g/mole Molar Mass = (40.08 g/mole)(3) + (30.97 g/mole)(2) + (16 g/mole)(8) = g/mole

Mole Conversions Learning Target:
Understand how molar mass relates to the number of moles and particles of a substance.

Particles (atoms, Formula units, molecules)
Divide by 6.02 X 1023 Multiply by 6.02 X 1023 Moles Multiply by molar mass from periodic table Divide by molar mass from periodic table Mass (grams)

3.5 dozen roses = ?? Roses 2.5 mol roses = ?? Roses (use Avogadro's #)

Problem Type #1 – Moles to Mass
Find the mass of mol of magnesium bromide.. Find the molar mass of the compound: Make the conversion:

Problem Type # 2– Mass to Moles
A bottle of copper (II) nitrate contains g of compound. How many moles of copper (II) nitrate are in the bottle?

Problem Type #3 – Moles to Particles
Determine the number of atoms that are in 0.78 mol of mercury.

Problem Type #4 – Particles to Moles
How many moles of zinc sulfate contain 5.40 x 1024 formula units?

Multi-step Mole Conversions
2.5 g Roses = ?? atoms of roses Atomic mass of 1 Rose is 3.0 g/mol

Multi-step Practice How many molecules are in 7.4 g of potassium phosphate?

Multi-step Practice How many grams of sodium bicarbonate are in 1.8 x 1023 formula units?

Molar Volume Definition: The volume of one mole of an ideal gas at standard conditions (STP) equal to 22.4 L. STP = standard temperature and pressure which is 0ºC and 1 atmospheric pressure (760 mmHg) 1 mole gas at STP = 22.4 L

Particles (atoms, Formula units, molecules)
Divide by 6.02 X 1023 Multiply by 6.02 X 1023 Moles Multiply by 22.4 L Divide by 22.4 L Volume (L)

Practice A container with a volume of 563L contains how many moles of air at STP? How many molecules of air?

Practice A chemical reaction produced 0.78 mol of H2 gas. What volume will the gas occupy at STP? How many molecules of H2? How many atoms of hydrogen?