Introductory Overview

Copyright © Myung-Hoon Kim

PowerPoint Lecture Presentation by Myung-Hoon Kim, GPC

Why Carbon was Chosen for Organisms by Mother Nature?

Copyright © Myung-Hoon Kim

PowerPoint Lecture Presentation by Myung-Hoon Kim, GPC

Characteristics of Living Organism (“Life”):

(1) Organization: ordered

(2) Exchange matter and energy with surroundings (environments)

- consume matter & energy to maintain (& move)

(3) Response to stimuli

(4) Reproduction

(5) Evolution: Undergo change to adapt to new environments which is changing all the time.

Brief history of Life on Earth: time before present (BP)4.6G BP, Earth formed (CO2, CO, CH4, NH3, OH2, H2) 4.3~3.8G BP, Age of Bombardment, Chemical Evolution

3.8G BP, First Prokaryote (Archeo-Bacteria ?)

3.5G BP, Blue-green Algae, (O2 ~ 0.2%)

3.2G BP, Bacteria O2 from Photosynthesis, but used up

2.1G BP, First Eukaryotes, O2 started to buildup

1.5G BP, Multicellular organism (O2 ~ 3%)

800-550M BP, Cryogenic Era (-40oC)

544M BP, Large, complex organisms (Cambrian Period starts: Explosion)

505M BP, Fish

480M BP, Land plants

400M BP, Insects

380M BP, Amphibians

330M BP, Reptiles, Birds

220M BP, Mammals

40M BP, Primates 5M BP, Hominids 2M BP, Homo

Brief history of mammals on Earth:

544M BP, Large, complex organisms (Cambrian Period starts)

505M BP, Fish

480M BP, Land plants

400M BP, Insects

380M BP, Amphibians

330M BP, Reptiles, Birds

220M BP, Mammals (Other Classes: Reptila, Amphibia)

50M BP, Primates (Other Orders: Carnivora, Insectivora)

5M BP, Hominids (Other Families: Lemur, Monkeys)

2M BP, Genus Homo diverged from Australopithecines (Homo Hablis started to use Stone Tool)

.25M BP, Homo Sapiens evolved replacing H. Erectus & H. Neanderthalensis

(in Asia) (in Europe)

0.05M BP, culture develop more rapidly

0.01M BP, Neolithic Age (Domestication of Animals, Plants), First Town

0.005 M BP, History started

6

- Greeks were the first to attempt to explain why chemical changes occur:

Thales(634-546 BC), “Water”

Heraclitus (535-475): “Recycle”

Empedocles (490-430):

“Water, Earth, Air, & Fire”

Democritus(455-370): “Atom”

- Alchemy dominated for 2000 years. Several elements discovered. Mineral acids prepared.

-Modern Science

Bacon(1561-26), Descartes(1596-50)

Newton(1642-27)

- Robert Boyle (1627-91): the first “chemist” - Performed quantitative experiments.

- Dalton (1766-44), Darwin(1809-82)

Brief History of Sciemce/Chemistry Natural Historyof Human

BP

220M : Mammals

(65M : KT Mass Extinction)

50M : Primates (65M)

2,000,000 : Home species diverged from A.

250,000 : Homo Sapience – Stone Tool.

80,000 : Fire (Cooking)

10,000 : Farming, Neolithic Age

7,000 : Copper

6,000 : Wine

5,000 : Bronze

3,300 : Iron

2,400: Atomic Theory(Democritus)

2,000: (Alchemy)

500: Metallurgy (Bauer),

Alchemy (Paracelsus )

400: Modern Chemistry:

~100: (Robert Boyle, Priestley

Lavoisier, Proust, Dalton …)

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(1)One of the most Abundant elements cosmically, #5 in mass %:

H He O N C Fe Ne Si Mg S

90.8 9.10 0.05 0.04 0.03 0.03 (%)

How?

(2)Its location in the PT (4th Group, 2nd Period) gives it a moderate electronegativity of 2.5.

- forms good Covalent Bond (rather than ionic bond) with others.

(3)One of few nonmetals that can form Four covalent bond per atom.

This provides it with many different way of combining with other

carbon atoms (and atoms of other elements). Branched bonds can

be formed to different directions

Why Carbon has been chosen by Mother Nature?

BP

Period

Group

Alkali M

etal

Noble G

as

Halogen

Alkali E

arth Metal

2.4

Terrestrial & Cosmic Abundance of Elements

Elements

Planet Earth:

“Earth is a tiny fragile spaceship in a vast universe.”

3.14(12,800km) = 40,200km3.14(8,000mi) = 25,000mi25,000mi/(70mi/hr) = 360hrs = 15days25,000mi/(600mi/hr) = 42hrs ~ 2daysAtmosphere : ~ 1% of the Diameter

Earth

• Lithosphere:

Crust: < 1% (Thin)

Everest: 8.85 km

Mantle, Core

•Hydrosphere:

(oceans) 3.8 km

Mariana Trench (11mi)

~ 0.2 %

• Atmosphere: ~1%:

30 km (99% of air)

extends to 120 km

• Biosphere:

World of

Living Organisms

Planet Earth

Composition Composition of Earth

Human Body : H2O 65%

2.4

Elements in Air (Atmosphere): N 78%, O 21%

Natural AbundanceElements in Earth’s crust (Lithosphere)

Elements in Human Body (Biosphere): H2O 65%

2.4

Elements in Air (Atmosphere): N 78%, O 21%

2.2

2.7

• Molecular compounds• nonmetals or nonmetals + metalloids• common names

• H2O, NH3, CH4, C60

• element further left in periodic table is 1st

• element closest to bottom of group is 1st

• if more than one compound can be formed from the same elements, use prefixes to indicate number of each kind of atom

• last element ends in ide

2.7

Then why not?

• September: 7th month

• October : 8th

• November: 9th

• December: 10th

2.7