RESOURCES SECTION C

Conservation and Moles

C.1 Big Ideas• Every Resources we use is obtained from these layers of the Earth…and

many are NON renewable

• Earth is composed of 3 layers: Atmosphere, Hydrosphere, Lithosphere

• Lithosphere has 3 sublayers: Crust, Mantle, Core

• Composition of Atmosphere:

• Composition of Hydrosphere:

• Composition of Lithosphere (Crust predominantly):

• Thickness of Lithosphere is comparable to skin of an apple

• No direct correlation between abundance of a resources and land area or population

• Some Nations or Regions control the majority of certain resources, like….

• The unequal balance of resources throughout the world has historically led to great advances…and to many wars

• The development of the US (we are only a little over 200 years old, compared to Countries like France, Great Britain, China…that’s chump change) as the PRE- EMINANT SUPERPOWER of this century is a direct result of the good fortune of plentiful and diverse resources

Earth

• The development of the U.S. as a major industrial nation can be greatly attributed to:________________

• Given the data that all resources are not distributed equally, what do you think about the idea of closing off our borders and decreasing international trade in an effort to decrease the likelihood of terrorist attacks? Immigration? What are some of the Pros and Cons to this idea?

• 2H2(g) + O2(g) 2H2O(l)

Section C.3 – The Mole…who cares?

• The mole is the unit we use to COUNT “things”• It’s a really BIG number, so we use it to count

really SMALL “things”…atoms, molecules…

Avogadro and his number1 mole = 6.02 x 1023 things1 mole = 602,000,000,000,000,000,000,000 thingsA “thing” can be ANYthing – pickles, eggs, turkeys, atoms, ions, molecules, …

Do you doubt the power of the mole?…it’s not called “Geoffrey’s number”…or “Jennifer’s number” now is it?…it’s

AVOGADRO’S Number… punks, and don’t you forget it!

….and Avocado…it’s a fruit

602,000,000,000,000,000,000,000

• Q. – How many eggs are in a dozen?• Q. – How many pickles are in a dozen?• Q. – How many pickles are in a ton of pickles?• Q. – How much paper is in a ream?• Q. – How many eggs are in a ream?• Q.- How many pickles are in a ream?• Q, - How many Helium atoms are in a ream? • Q. – How many eggs are in a mole?• Q. – How many pickles are in a mole?• Q. – How many Helium atoms are in a mole?!• Q. – How long do you think it would take you to drink 1 mole of

water? • Q. – How long would it take someone to count out 1 mole of water

molecules?

• Q. - Is the number of golf balls in a mole of golf balls the same as the number of bowling balls in a mole of bowling balls?

___________

• Q. – Is the mass of a mole of golf balls the same as the mass of a mole of bowling balls? ___________

The Number of Particles in a Mole Representative Particles – Whether Substance exists (commonly) as an atom, ion, or molecule formula units •    Exception – seven elements that exist as diatomic molecules• Molecular Compound – molecule •    Ionic Compounds – Formula unit

ATOMS VS. MOLECULES

1mole of Carbon atoms = 6.02 x 1023 atoms1 mole of CO2 molecules = 6.02 x 1023 molecules1 mole of CO2 molecules = 3 x 6.02 x 1023 total atoms

The Mass of a Mole of an Element

ATOMIC MASS = relative mass of one atom of a particular element• Measured in amu’s (atomic mass units)•Remember an atom of C is 12 times heavier than an atom of H Thus:

•Hydrogen = 1 amu•Carbon = 12amu.     •Oxygen has atomic mass = 16amu

Molar Mass = refers to the mass of a mole (6.02x 1023 ) of atoms of any element or compound. •Sometimes called gfm (gram formula mass)•Just replace the “amu” unit with “grams”

EX.       Oxygen has atomic mass = 16amu Oxygen has molar mass = 16g

= mass of 1 mole of atoms oxygen= mass of 6.02x 1023 atoms of oxygen

           

The Mass of a Mole of a Compound

• EX      – Find the mass of 1 mole of  Potassium iodide.

KI        K =      39.1g   I =  + 126.9 g

                           166.0g KI = 1 mole KI

Practice•

• Ex. – what is the mass of one mole of carbon atoms?

• Ex. – what is the mass of one mole of sodium atoms?

• Ex. What is the mass of 6.02 x 1023 oxygen atoms?

• Ex. – What is the mass of 3 moles of carbon atoms?

• Ex. – What is the mass of one mole of sodium chloride (NaCl) molecules?

• Ex. – What is the mass of 2 moles of sodium chloride (NaCl) molecules?

• Ex. – what is the mass of 2 moles of calcium chloride (CaCl2) molecules?

• Given the number of moles of a substance you can find the mass, and conversely given the mass you can find the number of moles – both by using the molar mass from the periodic table and dimensional analysis!!

• Ex. – Determine the number of moles in 25 g of NaCl

• Ex. – Determine the number of grams in 2.5 moles of NaCl

The Molar Mass of a Substance

EX.     Convert 7.20 mol of N2 03 into grams.

STEP 1: Calculate the (gfm)2 mole N     x    14.0 g N      =     28.0 g N

                        1 mole N

3 mole O    x     16.0 g O     =   + 48.0 g O                        1 mole O           76.0 g N2 O3

STEP 2: Use the (gfm) to convert from moles to grams

7.20 mole N2 O3 x  76.0 of N2 O3   =  5.47x 102 g N2 O3

                              1 mole N2 O3

Moles Practice Problems

1. How many molecules are there in 1.3 moles of H2O?

2. How much does 1.6 moles of NaCl weigh?3. What is the gfm of Al2(SO4)3?4. How much does a mole of Calcium weigh?5. Given 23 grams of NaOH, how many moles is

this?6. Given 23 grams of NaOH, how many

molecules is this?7. Given 4.2 x 1025 molecules of H2O, how many

moles is this?

Answers

1. 7.83 x 1023 molecules

2. 92.8 g

3. 342 g/mole

4. 40 g

5. 0.58 moles

6. 3.46 x 1023 molecules

7. 70 moles

RESOURCES DSources of Metals and Replacement Materials

MOLES LAB

C12H22O11

C6H12O6