How many is that?

kittens21 Couple of

How many is that?

meatballs

121 dozen

How many is that?

pencils1441 gross of

How many is that?

stars

1 mole of602,200,000,000,000,000,000,000

1 mole =

602,200,000,000,000,000,000,000

The Mole ?

The Mole ?

The Mole ?

The Mole !

602,200,000,000,000,000,000,0006.022 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10 x 10

6.022 x 1023

Avogadro’s Number6.022 x 1023 = “Avogadro’s Number”.

Amadeo Avogadro(1776-1855)

I didn’t discover it. It’s just named after

me!

What’s the mass of … 1 dozen kittens? (1 kitten weighs 3 lbs)

1 dozen 12 kittens 3 lbs

1 dozen 1 kitten36 lbs

What’s the mass of … 6 dozen meatballs? (1 meatball weighs

35 grams)

6 dozen 12 meatballs35 grams1 dozen 1 meatball

2520 grams

What’s the mass of …

3 gross pencils? (1 pencil weighs 15 grams)

3 gross 144 pencils 15 grams1 gross 1 pencil

6480 grams

What’s the mass of a mole???

Depends...

If it’s a mole of kittens, we take the mass of one kitten… and multiply by how many kittens.

3 lbs x 6.022 x 1023

If it’s a mole of Carbon atoms, it’s easier than that!

Carbon’s atomic mass = 12.0 grams/mole

SUPER IMPORTANT CONCEPT!

Molar Mass = the mass (in grams) of 1 mole (6.022 x 1023) of anything

Finding the molar mass of an element is pretty easy!• Take it’s atomic mass and make the units

“X grams/1 mole of X atoms”

Try it: Molar mass of Lithium? Helium?

Iron?

6.94 grams/1 mole Li atoms4.00 grams/1 mole He atoms55.85 grams/1 mole Fe atoms

Calculations with Moles:Converting moles to grams

How many grams of lithium are in 3.50 moles of lithium?

3.50 mol Li = g Li1 mol Li

6.94 g Li 24.29

Calculations with Moles:Converting grams to moles

How many moles of lithium are in 18.2 grams of lithium?

18.2 g Li= mol Li

6.94 g Li

1 mol Li 2.62

Calculations with Moles:Using Avogadro’s Number

How many atoms of lithium are in 3.50 moles of lithium?

3.50 mol

= atoms1 mol

6.02 x 1023 atoms 2.11 x 1024

Calculations with Moles:Using Avogadro’s Number

How many atoms of lithium are in 18.2 g of lithium?

18.2 g Li

= atoms Li

1 mol Li 6.022 x 1023 atoms Li

1.58 x 1024

6.94 g Li 1 mol Li

(18.2)(6.022 x 1023)/6.94

You try it!

If you had 107.92 grams of Aluminum foil, how many moles of Aluminum are there?

= moles Al atoms

You try it!

If you had 3.011 x 1023 atoms of Calcium, how many grams of Calcium are there?

= grams Ca

What about for compounds, you ask???

Since a compound is more than one atom bonded, just add the masses of all the atoms there

12.01 g + 2(16.00 g) =44.01 g

One mole of CO2 (6.02 x 1023 molecules) has a mass of 44.01 grams

Example: Carbon Dioxide (CO2)

You try it!

1 mole of NaCl would weigh exactly how many grams?

= grams NaCl

6 moles of NaCl would weigh exactly how many grams?

= grams NaCl

You try it!

How many grams of Dihydrogen Monoxide are in 6.022 x 1023 molecules of Dihydrogen Monoxide?

= grams H2O

Standard Molar Volume

Equal volumes of all gases at the same temperature and pressure contain the same number of molecules.

- Amedeo Avogadro

At STP (Standard Temperature and Pressure):Standard Temperature = 0˚ C

Standard Pressure = 1 atmosphere

1 mole of a gas occupies 22.4 liters of volume

Calculations with Moles:Using Standard Molar Volume

How many moles of hydrogen are in 100 L of hydrogen at STP?

100 L = mol

22.4 L

1 mol4.46

Calculations with Moles:Using Standard Molar Volume

How many liters are occupied by 3 moles of oxygen gas at STP?

3 mol = L

1 mol

22.4 L67.2

You try it!

16 moles of Cl2 gas would occupy how many liters?

= L Cl2

= grams Cl2

16 moles of Cl2 gas would have a mass of how many grams?

Do it all at once!

35 grams of carbon tetrafluoride gas would occupy how many liters?

1 mol CF4 = L CF4

1 mol

22.4 L

8.988.01 g

35 g

You try it!

1373 grams of N2 gas would occupy how many liters?

…………………………………………………..= L N2

Mole Relationship

s

Mole

Atomsor

molecules

Liters

Grams

6.02 x 10 23

Ato

mic

Mass

22. 4

L22.4 L