Mole

The Mole

Unit 7

What is a Mole?

A relative quantity used for tiny particles.

1 pair of socks = __ socks
1 dozen eggs = __ eggs
1 gross of goblins = __ goblins
1 great gross of peanuts = __ peanuts
1 score of years = __ years
1 mole of an item = __ items

Going to use this number
all trimester!!!

What is a Mole?

A relative quantity used for tiny particles.

1 pair of socks = _2_ socks
1 dozen eggs = _12_ eggs
1 gross of goblins = _144_ goblins
1 great gross of peanuts = _1728_ peanuts
1 score of years = _20_ years
1 mole of an item = _6.022 x 1023_ items

Going to use this number
all trimester!!!

Practice: What is a mole?

A mole of pennies: _6.022 x 1023 pennies_

A mole of grains of sand: _6.022 x 1023 grains of sand_

A mole of hockey pucks: _6.022 x 1023 hockey pucks_

Fun fact:If we were able
to count atoms at the rate
of 10 million per second,

it would take about 2

billion years to count the

atoms in one mole

Multiple Choice

What is Avogadro's number?

• 6.022 x 10²³

• 1 mole

• 600 million

• 6.02

Multiple Choice

How many moles are in 6.022 x 10²³ molecules of H₂O?

• 1 mole

• 2 moles

• 6.02 moles

• 602000000000000000000000 moles

Molar Mass

●Molar Mass - the mass of ____________ of a pure substance

●Units - __________

●Is found on the ___________ rounded to ____ decimal places

●C:

●C6H12O6

●Calcium Hydroxide

Molar Mass

●Molar Mass - the mass of one mole of a pure substance

●Units - g/mol

●Is found on the periodic table rounded to two decimal places

●C: 1 x 12.01 = 12.01 g/mol

●C6H12O6 C: 6 x 12.01 = 72.06

H: 12 x 1.01 = 12.12
O: 6 x 16.00 = 96.00

180.18 g/mol

●Calcium Hydroxide Ca+2 OH-1⇒ Ca(OH)2

Ca: 1 x 40.08 =

40.08

O: 2 x 16.00 =

32.00

H: 2 x 1.01 =

+2.02
74.10 g/mol

Multiple Choice

The mass of one mole of substance is called...

• molecular mass
• mole constant
• molar mass
• atomic weight

Multiple Choice

What is the molar mass of sodium?

• 11
• 22.99

• 45.98
• 3

Multiple Choice

Molar mass is in units of ________.

• grams
• grams/mole
• mole
• moles/gram

Practice

1.

Mg -

2.

MgCl2 -

3.

PbSO4 -

Practice

1.

Mg - 1 x 24.31 = 24.31 g/mol

2.

MgCl2 - Mg: 1 x 24.31 = 24.31

Cl: 2 x 35.45 = +70.90

95.21 g/mol

3.

PbSO4 - Pb: 1 x 207.20 = 207.20

S: 1 x 32.07 =

32.07

O: 4 x 16.00 = +64.00

303.27 g/mol

Multiple Choice

What is the molar mass of table salt (NaCl)?

• 116.886 g/mol
• 35.453 g/mol
• 22.990 g/mol
• 58.443 g/mol

Multiple Choice

Calculate the molar mass for Al(OH)₃

• 78.0 g/mol

• 72 g/mol

• 28 g/mol

• 25 g/mol