Factor Label Practice

• http://www.guinnessworldrecords.com/

The Mol…• Just another unit of measurement• In one mole of atoms or molecules, there are

6.022 x 10 23 atoms or molecules (HCl or S)• Just like in one dozen eggs, there are 12 eggs.• Atoms and molecules are EXTREMELY small,

that is why the mol is such a BIG number • The mol makes it easier to represent such a

large numberYou wouldn’t express the distance to

California in centimeters, you would express it in kilometers

Let’s practice

• How many H atoms are in 1 mole?

• How many molecules of CO are in 1 mol of CO?

• How many moles of sodium are in 2.9 x 10 22 atoms of sodium?

Using your calculator

• Use the EE button!– EE means ‘times 10 to the ___ power”– 1.0 EE 9 = 1.0 x 10 9

More practice

• How many sodium atoms are in 2.5 moles of sodium?

• How many molecules of carbon dioxide are in 0.5 moles of carbon dioxide? How many atoms is this?

• How many moles are in 1 billion atoms oflithium?

More practice

• How many atoms are in 3.0 moles of osmium?

• How many molecules of sulfur monoxide are in .75 moles?

• How many moles are in 2.3 x 10 24 atoms of Cu?

Molecules and atoms

• How many oxygen atoms are in 1 molecule of O2?

• How many hydrogen atoms are in 1 molecule of C3H8? How many carbon atoms are present?

• To go from molecules to atoms→ count how many of each atom are in the molecule

Practice• How many hydrogen atoms are in 1

methane molecule?• How many nitrogen atoms are in 1 lead

II nitrate molecule?

Molar Mass• This is also known as gram atomic

mass (for an atom), gram formula mass (for an ionic compound) and gram molecular mass

• The mass of 1 mole of an atom or a molecule

Gram atomic mass

• The mass (g) of 1 mole of an atom → Use the periodic table

• GAM of – carbon is 12.0 g– oxygen is 16.0 g– Go to the 10ths

• What is the GAM of – Iodine– Calcium?

Gram Molecular Mass

• What is formula for:– sulfur dioxide?– Diphosphorous

pentoxide?GMM = add up

atomic masses

Gram Formula (ionic) Mass

What is the GFM of KCl?Cu(NO3)2?

QUIZ: Please do on a half a sheet of paper

1. How many grams of water are in 2.0 mols of water?

2. How many moles of Mg is 1.25 x 10 23 atoms of Mg? How many grams is this?

3. How many atoms are in 2.8 x 10 24 molecules of SiO2? How many grams is this?

4. How many liters does 8.5 grams of oxygen gas occupy? (Assume STP)

Hint for homework

• Representative particle = atoms or molecules.

Mole / Volume Relationship

1 mol of gas at STP = 22.4 Liters

STP = Standard Temperature and Pressure

Standard Temp = 0 oC

Standard Pressure = 101.3 kPa (kiloPascals) or 1.0 atm (atmospheres)

1. How many liters of space does 1.73 mol of NH3 gas take up at STP?

1.73 mol NH3 1 mol NH3

22.4 L NH3 = 38.7 L NH3

2. How many moles of O2 are equal to 9.6 liters?

9.6 L O2

22.4 L O2

1 mol O2 = 0.43 mol O2

Practice for test

• Collect 2.0 moles of water. How many mL is this?

• Collect 0.75 moles of potassium sulfate.• Collect 8.0 x 10 24 molecules of barium

chloride.• Collect 3.0 x 10 23 atoms of aluminum.• Collect 2.0 grams of sodium chloride.

How many moles is this? How many molecules?

Homework

Monday’s homework in Unit Calendar

Page 186 #24-27; Page 198 #55 a-c, 57, 59

Worksheet 7.1