Topics for Today Burning a gallon of gasoline… Where does my gasoline come from?

Readings for Today 3.6 Quantitative Concepts: Mass 3.7 Quantitative Concepts: Molecules and Moles

Topics for Friday Exam #2

Topics for Monday Greenhouse Earth!

Readings for Monday 3.1 The Earth’s Energy Balance 3.2 Gathering Evidence 3.3 Molecules: How they Shape Up

Topics for Wednesday Greenhouse Gases: How do they keep us warm?

Readings for Wednesday 3.4 Vibrating Molecules and the Greenhouse Effect

Announcements!!!

HW 3 is due one week from today! Isomers…

Announcements!!! Today is March 14!! Happy pi day!! (3.14) But wait, there’s more! Happy Birthday!

Bring back your radon disks!!

Topics for Today Burning a gallon of gasoline… Where does my gasoline come from? What do we get when we burn a gallon of gasoline?

DEMO???

“Smoke on the water, a fire in the sky…”

Why don’t hydrocarbons mix with water? CH 3 -C-CH 2 -CH-CH 3 CH 3 O — H H

Topics for Today Burning a gallon of gasoline… Where does my gasoline come from? What do we get when we burn a gallon of gasoline?

Chemical Math… + = ? X

What weighs more? A ton of feathers? Or a ton of bricks?

What weighs more? A pound of gold? Or a pound of oxygen?

What weighs more? Or a pound of oxygen? A pound of hydrogen?

NOW!! A ton of feathers A ton of bricks More bricks or more feathers?

10 grams of oxygen 10 grams of hydrogen

10 grams of oxygen 10 grams of hydrogen More H 2 or O 2 molecules?

O 2 = 32 H 2 = 2

Oxygen (O 2 ) has 16 times greater mass than hydrogen (H 2 ) For a given mass… O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 There are 16 times more H 2 molecules than O 2 molecules H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2 H2H2

1 mole of H atoms = 1 gram 1 mole of H 2 molecules = 2 grams 1 mole of O atoms = 16 grams 1 mole of O 2 molecules = 32 grams And so on…

Atom and Molecule Counting 1 mole of H 2 has the same number of molecules as 1 mole of O 2 (or anything, for that matter)

What is a mole? What is a dozen? 12 of anything 6.02 x of anything

1 mole of H 2 O = ???? g 1 mole of CO 2 = ???? g 1 mole of H 2 = 2 g 1 mole of O 2 = 32 g All contain the same number of molecules (one mole)!!!

1 mole of H 2 O = 18 g 1 mole of CO 2 = 44 g 1 mole of H 2 = 2 g 1 mole of O 2 = 32 g All contain the same number of molecules (one mole)!!!

Easy Question Chemically speaking, what does it mean to “burn” something?

Reacts with O 2 ! Combustion ! C + O 2  CO 2 S + O 2  SO 2 N 2 + O 2  2NO H 2 + O 2  ??? Write the reaction for the combustion of H 2

Reacts with O 2 ! Combustion ! C + O 2  CO 2 S + O 2  SO 2 N 2 + O 2  2NO 2H 2 + O 2  2H 2 O

+ + O2O2 2H 2 O2H 2 How do we read this equation?

+ + O2O2 2H 2 O2H 2 How do we read this equation? 2 molecules of H molecule of O 2  2 molecules of water 2 dozen molecules of H dozen molecules of O 2  2 dozen molecules of water 2 moles of H mole of O 2  2 moles of water 2 grams of H gram of O 2  2 grams of water

How many grams of water do we get if we burn 10 g of H 2 ? + + O2O2 2H 2 O2H 2

What do we know? + O2O2 2H 2 O2H 2 2 moles of H 2 will produce 2 moles of water… How many grams of water do we get if we burn 10 g of H 2 ?

Step 1… How many moles H 2 in 10 grams of H 2 ? 10g H 2 2g H 2 1 mole H 2 = 5 mole H 2 GRAMSMOLES

Step 2… How many moles H 2 O are formed from H 2 ? 10g H 2 2g H 2 1 mole H 2 GRAMS H 2 MOLES H 2 + O2O2 2H 2 O2H 2 2 mole H 2 2 mole H 2 O MOLES H 2 O = 5 mole H 2 O MUST look at balanced chemical equation!!!

Step 3… How many grams of water? 10g H 2 2g H 2 1 mole H 2 GRAMS H 2 MOLES H 2 + O2O2 2H 2 O2H 2 2 mole H 2 2 mole H 2 O MOLES H 2 O 1 mole H 2 O 18g H 2 O GRAMS H 2 O = 90 g H 2 O

GRAMS H 2 MOLES H 2 MOLES H 2 O GRAMS H 2 O + O2O2 2H 2 O 2H 2 Summary

Topics for Today What is in my gasoline? Burning a gallon of gasoline… What do we get when we burn a gallon of gasoline?

Chemical formula? C 7 H 16 CH 3 CHCH 2 CH 3 2-methylhexane CH 3

1. Balanced Chemical Equation C 7 H 16 +O2O2 H2OH2O+CO 2 Balanc e!!

1. Balanced Chemical Equation C 7 H O 2 8H 2 O+7CO 2 How many grams of CO 2 do we get when we burn a gallon of gasoline?

GRAMS H 2 MOLES H 2 MOLES H 2 O GRAMS H 2 O Summary

GRAMS H 2 MOLES H 2 MOLES H 2 O GRAMS H 2 O Summary Gallon?

Density Density gasoline = 0.7 grams per mL

1 gallon = 3,790 mL

DENSITY= MASS GASOLINE VOLUME GASOLINE

0.7 g/mL= MASS GASOLINE 3,790 mL GASOLINE Cross multiply, and… 2,650 g gasoline!! PHEW!

GRAMS HC MOLES HC MOLES CO 2 GRAMS CO 2 Summary Gallon = 2,650 grams!

2650 g C 7 H g C 7 H 16 1 mole C 7 H 16 GRAMS HCMOLES HC 1 mole C 7 H 16 7 mole CO 2 MOLES CO 2 1 mole H 2 O 44g CO 2 GRAMS CO 2 = 8,162 g CO 2 ! C 7 H O 2 8H 2 O+7CO 2

Burn 1 gallon of gasoline… About 18 lbs of CO 2 is emitted!

Practice on your own for methane, ethane, octane, etc!!

Where does our gasoline come from?

Crude Oil C.H. Middlecamp What is crude oil?

A collection of thousands of different hydrocarbons ranging from around C4 up to about C30 and higher. Crude Oil

A collection of thousands of different hydrocarbons ranging from around C4 up to about C30. Crude Oil Where did the oil come from?

The gradual decay of plant and animal matter over the past 500 million years or so

Who are the top producers of crude oil in the world?

What is a barrel?

1 barrel = 42 gallons of crude oil

Top 5 Oil Producers Saudi Arabia Russia United States Iran China

Top 5 Oil Producers Saudi Arabia Russia United States Iran China

US Oil Statistics The US produces 5,200,000 barrels / day Accessed March 11, 2007 The US consumes 20,000,000 barrels / day

Top US crude oil supplier? Canada Supplies 1,633,000 barrels / DAY!!

How long will it last?

M. King Hubbert "Our ignorance is not so vast as our failure to use what we know."

“When we consider that it has taken 500 million years of geological history to accumulate the present supply of fossil fuels, it should be clear that, although the same geological processes are still operative, the amount of fossil fuels that is likely to be produced over the next few thousand years is inconsequential.” Nuclear Energy and the Fossil Fuels – M. King Hubbert

Published a paper in 1949 predicting that the US production of oil would peak in Why?

Published a paper in 1949 predicting that the US production of oil would peak in Why? How close was his prediction?

What about the rest of the world?

Some Norwegian Oil Fields

Projected…

Some UK Oil Fields

Projected…

Billion Barrels / Year

“Just as certain as death and taxes is the knowledge that we shall one day be forced to learn to live without oil.” -BBC News

“The fossil fuels, which include… coal, petroleum, and natural gas have all had their origins from plants and animals existing upon the earth during the last 500 million years.” Nuclear Energy and the Fossil Fuels – M. King Hubbert