I II III IV

The Mole

I. Molar Conversions

A. What is the Mole?

A counting unit Similar to a dozen, except

instead of 12, it’s 602 billion trillion 602,000,000,000,000,000,000,000

6.02 X 1023 (in scientific notation) This number is named in honor

of Amedeo Avogadro (1776 – 1856)Amedeo Avogadro (1776 – 1856),

1 mole of hockey pucks would equal the mass of the moon!

A. What is the Mole?

1 mole of pennies would cover the Earth 1/4 mile deep!

1 mole of basketballs would fill a bag the size of the earth!

How does a Mole relate? 1 Mole of anything has 6.02 x 1023

particles If I had 1 mol of cookies, how many

cookies would I have? If I had 1 mol of cars, how many cars

would I have? If I had 1 mol of Aluminum, how many

atoms I have? Note that the NUMBER is always the

same, but the MASS is very different!

1 mole of Carbon = 6.02 x 1023 atoms (Individual

elements are measured in atoms)

1 mole of H2O= 6.02 x 1023 molecules (Covalent

compounds are measured in molecules)

1 mole of NaCl = 6.02 x 1023 “formula units”

(Ionic compounds are measured in ions)

6.02 x 1023 Na+ ions and

6.02 x 1023 Cl– ions

The “Units” of MolesThe “Units” of Moles

1. Number of atoms in 0.500 mole of Ala) 500 Al atoms

b) 6.02 x 1023 Al atomsc) 3.01 x 1023 Al atoms

2.Number of moles of S in 1.8 x 1024 S atomsa) 1.0 mole S atomsb) 3.0 mole S atomsc) 1.1 x 1048 mole S atoms

Learning CheckLearning Check

Molar Mass Describes the mass (how heavy) 1 mole of

an element or compound is.

Atomic mass tells the:

Atomic Mass Units (AMU)

Used to determine the mass of a single

element.

Grams per mole (g/mol) used to describe the mass of one mole of a

chemical compound.

Typically rounded to 2 decimal places

Find the molar mass – Round to two decimal places. It is

important for significant digits!

Learning Check!Learning Check!

A.1 mole of Br atoms

B.1 mole of Sn atoms

= 79.90 g/mol

= 118.71 g/mol

Molar Mass Examples for molecules and compounds: Water

sodium chloride

H2O

2(1.01) + 16.00 = 18.02 g/mol

NaCl 22.99 + 35.45 = 58.44 g/mol

A. Molar Mass of K2O = ? g/mol

B. Molar Mass for Al(OH)3 = ?

Learning Check!Learning Check!

Molar Conversions (Road Map)

molar mass

(g/mol)

Gram Gardens

Mole Island

Particle Palace

6.02 1023

(particles/mol)

Grams to Moles

How many moles of carbon are in 26 g of carbon?

26 g C 1 mol C

12.01 g C= 2.2 mol C

Grams to Moles

How many moles of oxygen are in 85 g of Oxygen?

85 g O 1 mol O

16.00 g O= 5.3 mol O

Moles to Grams

How many grams of oxygen are in 0.25 moles of oxygen?

0.25 mol O 16.00 g O

1 mol O= 4.0 grams O

Moles to Grams

How many grams of carbon are in 3.45 moles of carbon?

3.45 mol C 12.01 g C

1 mol C= 41.4 grams C

Moles to Particles

How many molecules are in 2.50 moles of C12H22O11?

2.50 mol6.02 1023

molecules

1 mol= 1.51 1024

molecules C12H22O11

Particles to Moles

How many moles are in 1.505 x 1023 molecules of HCl?

1 mol1.505 1023

molecules6.02 1023

molecules

= 0.2500 Moles HCl