The Mole

Chemistry

First Something Familiar

What do the following items have in common?

What common traits did you notice?

Look at these next photos and see if any would belong in the same category

as the last set of photos

Think about whether or not they have the same traits as you found to be common in the last set

Hopefully, you found that none of the photos represent a dozen

Thus, they are NOT like the preceding photos that depicted “dozen”

Now, Something Not Familiar

What do the following items have in common?

Use your note-taking template to list some common traits for the examples you see

32 grams of Sulfur

Examples of the Mole

What common traits did you notice?

Take a Look at the Following Examples

There will be columns, just like on your note sheet, that have positive

and negative examples

List common traits you see in the positive examples and find reasons why the negative

examples are unlike the positive ones

Examples of the MolePositive Examples

12g of Carbon16g of Oxygen1g of Hydrogen44g of CO2

18g of H2O

6.02 x 1023 atoms of Carbon, Hydrogen or Oxygen

Negative Examples12amu of Carbon16amu of Oxygen1amu of Hydrogen44amu of CO2

18amu of H2O

(g) = gram

(amu) = atomic mass unit

1 amu is equal to 1.6611x10-24 grams (very small amount of a gram)

Let’s share some ideas aloud…

Definition of the Mole

Using your common traits from the positive examples and your “lack of” common traits from the negative attributes, create a working definition of the Mole

Now, Take a Look at these Examples

Like the last set, find traits that are similar and unlike between the

groups

Look for attributes that

may not have appeared in the last set and compare to your working definition

More Examples of the Mole

Positive Examples 6.02 x 1023 atoms of Nitrogen 6.02 x 1023 molecules of Water 6.02 x 1023 atoms of Carbon

Negative Examples1 atom of Nitrogen1 molecule of Water1 atom of Carbon

(g) = gram

(amu) = atomic mass unit

1 amu is equal to 1.6611x10-24 grams (very small amount of a gram)

Definition of the Mole

Did you find anything in the last slide that was different or new?

Did the common traits found in those examples of the mole match your definition?

Did you have to change your definition at all?

Definition of the MoleIf your common attributes led you to a working

definition that looks something like this, you’ve got the concept!!

• A mole is a number—it is a constant—a mole will always equal 6.02 x 1023

• It relates the mass of a single atom in amu to the mass in grams

• Avogadro was a scientist who discovered that there was a special relationship between mass of an atom in amu to its mass in grams

• This relationship is that the mass of an atom or molecule in grams contains exactly 6.02 x 1023 particles—no matter the kind of particle; thus, the quantity was defined and named after him.

• This number is important in chemistry, but it is a mouthful to say all the time.

• So, we have a term, the mole, which is defined as Avogadro’s number, or 6.02 x 1023, of any substance

I’m here to tell you all about moles! What they

mean, how to use them and how to calculate them. Check out my diagram

below, then we’ll discuss more in detail.

Mr. Mole

MolesMoles

Number of ParticlesNumber of Particles

MassMass

X X

mole

particlesx

1

1002.6 23 X X

particlesx

mole231002.6

1

mole

MolarMass

1 X X

mole

MolarMass

1 X X

MolarMass

mole1

Let’s Try Some Problems Involving Moles

Critical Thinking Questions

1. According to the periodic table, a single carbon atom has a mass of 12.011 amu.

How many carbon atoms does it take to equal 12.011 grams?

2. According to the periodic table, a single carbon atom has a mass of 12.011 amu.

How many carbon atoms does it take to equal 12.011 grams?

3. According to the periodic table, a single Oxygen atom has a mass of 15.999amu. How many oxygen atoms does it take to equal 15.999 grams?

4. Compare your answers to questions 1, 2 and 3.

Critical Thinking Questions

1. According to the periodic table, a single carbon atom has a mass of 12.011 amu.

How many carbon atoms does it take to equal 12.011 grams?6.02x1023 atoms (1 mole)

2. According to the periodic table, a single carbon atom has a mass of 12.011 amu.

How many carbon atoms does it take to equal 12.011 grams?6.02x1023 atoms (1 mole)

• According to the periodic table, a single Oxygen atom has a mass of 15.999amu. How many oxygen atoms does it take to equal 15.999 grams?

6.02x1023 atoms (1 mole)

• Compare your answers to questions 1, 2 and 3. They are all equal to 6.02x1023 atoms (1 mole)

Now that you’ve got down the Now that you’ve got down the mole concept and you’ve seen mole concept and you’ve seen

it in action, let’s it in action, let’s

to the independent practice! to the independent practice!

Let’s check and make sure you’re getting this “mole” thing

down.

Mr. Mole

If I have 1 mol of carbon, how many atoms do I have? If I have 1 mol of water, how many molecules do I

have? If I have 1 mol of Ca2+ ions, how many ions do I have?

If I have 1 mol of salt, how many formula units of salt do I have?

If I have 1 mol of donuts, how many donuts do I have?If I have 6.02x1023 M&M’s, how much candy do I have?If I have 6.02x1023 French fries, how much potato do I

have?If I have 6.02x1023 molecules of carbon monoxide, how

much CO do I have?

Rock n’ Mole

A mole is a unit, or have you heard,Containing six times ten to the twenty-third,That's a six with twenty-three zero's at the end,Much too big a number to comprehend.