1. Measuring Matter Today you’ll need: Periodic Table Calculator
The Mole: Basic Concepts
Measuring Matter
Today you’ll need:
Periodic Table
Calculator
Note taking materials

2. Do a dozen eggs weigh the same as a dozen feathers?
The Mole: Basic Concepts
The Mass of a Mole
Do a dozen eggs weigh the same as a dozen feathers?
Nope! Does a mole of one element weigh the same as a mole of a different element?
Nope!

3. Molar mass: The mass in grams of one mole of any pure substance.
The Mole: Basic Concepts
The Mass of a Mole
Molar mass: The mass in grams of one mole of any pure substance.
atomic mass (g)
molar mass =
1 mol

4. The Mass of a Mole Carbon. Atomic mass: 12.011 amu
The Mole: Basic Concepts
The Mass of a Mole
Carbon.
Atomic mass: amu
Molar mass: g/mol
Manganese
Atomic mass: amu
Molar mass: g/mol

5. Molar mass of a compound
The Mole: Basic Concepts
Molar mass of a compound
Molar mass of a compound: the mass of a mole of the compound.
Molar mass of NH3 =
molar mass of N + 3(molar mass of H)
Molar mass of NH3 =
g/mol + 3(1.008 g/mol) = g/mol

6. Practice: Finding Molar Mass
Find the molar mass of the following:
NaOH
C2H5OH
Sr(NO3)2
(NH4)3PO4
40.00 g/mol NaOH
46.07 g/mol C2H5OH
g/mol Sr(NO3)2
40.00 g/mol (NH4)3PO4

7. Examples Molar mass as a conversion factor
a) Calculate the mass of moles of calcium.
0.625 mol Ca
g Ca =
25.0
g Ca
1 mol Ca
Use molar mass to convert mol to g

8. Examples Molar mass as a conversion factor
b) A roll of copper wire has a mass of 848 g. How many moles of copper are in the roll?
848 g Cu
1 mole Cu =
13.3
mol Cu
g Cu
Use molar mass to convert g to mol

9. Moles of a compound to Mass
The Mole: Basic Concepts
Moles of a compound to Mass
c) Example: What is the mass of 2.50 moles of (C3H5)2S ?
Molar Mass:
g/mol (C3H5)2S
2.50 mol (C3H5)2S
g (C3H5)2S
= g (C3H5)S
285.3
1 mol (C3H5)2S
Use molar mass to convert mol to g

10. Converting Mass of a Compound to Moles
The Mole: Basic Concepts
Converting Mass of a Compound to Moles
d) How many moles of water are in kg of water?
Molar Mass:
g/mol H2O
1.000 kg H2O
1000 g H2O
1 mol H2O
= mol H2O
= mol H2O
g H2O
1 kg H2O
Convert kg to g
Use molar mass to convert g to mol

11. Practice Convert to moles: 1) 25.5 g Ag 2) 300.0 g S 3) 319 g H2SO4
Convert to grams:
4) 3.57 mol Al
5) 42.6 mol Si
6) 4.35x10-2 mol ZnCl2
0.236 mol Ag
96.3 g Al
9.355 mol S
1.2x103 g Si
3.25 mol H2SO4
5.93 g ZnCl2